Validation of the Choking Risk Assessment and Pneumonia Risk Assessment for adults with Intellectual and Developmental Disability (IDD)

Research in Developmental Disabilities 69 (2017) 61–76

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Research in Developmental Disabilities journal homepage: www.elsevier.com/locate/redevdis

Validation of the Choking Risk Assessment and Pneumonia Risk Assessment for adults with Intellectual and Developmental Disability (IDD)

MARK

⁎

Justine Joan Shepparda, , Georgia A. Malandrakib, Paula Piferc, Jill Cuffd,1, Michelle Trochea, Bronwyn Hemsleye, Susan Balandinf, Avinash Mishraa,2, Roberta Hochmang a

Department of Biobehavioral Sciences, Teachers College, Columbia University, New York, NY, USA Department of Speech, Language, and Hearing Sciences, Purdue University, West Lafayette, IN, USA c Woodward Resource Center, Department of Speech and Hearing, Woodward, IA, USA d Glenwood Resource Center, Department of Occupational Therapy, Glenwood, IA, USA e School of Humanities and Social Sciences, The University of Newcastle, Newcastle, NSW, Australia f School of Health and Social Development, Deakin University, Melbourne, VIC, Australia g Woodbridge Developmental Center, Department of Speech and Hearing (retired), Woodbridge, NJ, USA b

AR TI CLE I NF O

AB S T R A CT

Number of reviews completed is 2

Background: Risk assessments are needed to identify adults with intellectual and developmental disability (IDD) at high risk of choking and pneumonia. Aim: To describe the development and validation of the Choking Risk Assessment (CRA) and the Pneumonia Risk Assessment (PRA) for adults with IDD. Methods: Test items were identified through literature review and focus groups. Five-year retrospective chart reviews identified a positive choking group (PCG), a negative choking group (NCG), a positive pneumonia group (PPG), and a negative pneumonia group (NPG). Participants were tested with the CRA and PRA by clinicians blind to these testing conditions. Results: The CRA and PRA differentiated the PCG (n = 93) from the NCG (n = 526) and the PPG (n = 63) from the NPG (n = 209) with high specificity (0.91 and 0.92 respectively) and moderate to average sensitivity (0.53 and 0.62 respectively). Further analyses revealed associations between clinical diagnoses of dysphagia and choking (p = 0.043), and pneumonia (p < 0.001). Conclusions: The CRA and PRA are reliable, valid risk indicators for choking and pneumonia in adults with IDD. Precautions for mitigating choking and pneumonia risks can be applied selectively thus avoiding undue impacts on quality of life and unnecessary interventions for low risk individuals.

Keywords: Intellectual disability Adults Risk assessment Dysphagia Choking Pneumonia

1. Introduction Choking and pneumonia are serious health and safety concerns for adults with intellectual and developmental disability (IDD) (Chadwick & Jolliffe, 2009; Guthrie & Stansfield, 2017; Morad, Kandel, & Merrick, 2009). Aspiration is a contributing cause for ⁎

Corresponding author at: 111 Chincopee Road, Lake Hopatcong, NJ 07849, USA. E-mail address: [email protected] (J.J. Sheppard). 1 Jill Cuff is now at Cuff & Associates, LLC, Malvern, IA. 2 Avinash Mishra is now at Department of Rehabilitation Medicine, Columbia University Medical Center, New York, NY. http://dx.doi.org/10.1016/j.ridd.2017.07.016 Received 15 December 2016; Received in revised form 16 March 2017; Accepted 23 July 2017 0891-4222/ © 2017 Elsevier Ltd. All rights reserved.

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pneumonia (Langmore et al., 1998). Choking and aspiration occur as a consequence of failure in airway protection associated with swallowing (Troche, Brandimore, Godoy, & Hegland, 2014) and may be resolved as a non-fatal but harmful event or can be fatal. The mechanisms for this failure are varied. Choking refers to the individual’s attempt to clear an airway obstruction lodged, typically, where the airway narrows at or above the vocal folds or in the trachea below the vocal folds. Furthermore, indirect tracheal obstruction may occur when there is blockage in the esophagus compressing the trachea. The signs of choking are immediate and vary depending on whether the obstruction is partial or complete. They include gagging, coughing, inability to vocalize, cyanosis, anxiety, and loss of consciousness (Samuels & Chadwick, 2006; Sparks, 2016). Aspiration associated with swallowing refers to entry of bolus material below the level of the true vocal folds and into the trachea. This may occur prior to initiating swallowing, during swallowing or directly after swallowing. If the individual is unable to expel aspirated material, the outcome is passage of the material into the lungs and potential pulmonary infection (Martin et al., 1994; Ramsey, Smithard, & Kalra, 2005; Rogers, Stratton et al., 1994). Aspiration may be associated with swallowing food, drink, saliva or medications. In contrast with choking, aspiration related morbidity and mortality are delayed by hours or days from the event and may have cumulative effects over repeated episodes. Troche, Brandimore, Godoy et al. (2014) proposed a framework for airway protection in which awareness of the sensation of aspiration results in urge to cough, a cortically-mediated response followed by the reflexive cough response. Thus, the cough expels the aspirate from the airway into the oropharynx for swallowing or the oral cavity for expulsion. This model may be expanded to include choking, as penetration into the upper airway may begin in the oropharynx with a gag response and progress to cough as the material moves distally into the larynx (i.e., choking) and thence through the glottis to the trachea and into the lungs as “aspirate.” In healthy individuals, an effective cough clears aspirate material from the airway. However, higher cough reflex thresholds and weaker cough responses, along with absence of cough commonly seen in adult onset dysphagia and individuals with IDD and dysphagia may result in ineffective clearance (Chadwick & Jolliffe, 2009; Troche, Brandimore, Okun et al., 2014). Furthermore, adults with IDD may be at a cognitive disadvantage for timely appreciation of the urge to cough and the cortical to brainstem activation of the reflexive cough (Troche, Brandimore, Godoy et al., 2014; Troche, Brandimore, Okun et al., 2014). It is this link between asphyxiation and aspiration and the high incidence of choking and pneumonia in adults with IDD that motivated this risk management study. 1.1. Incidence of choking and pneumonia in IDD Reducing choking mortality in individuals with IDD is a frequently occurring topic in health care and disability literature (Carter & Jancar, 1994; Samuels & Chadwick, 2006; Thacker, Abdelnoor, Anderson, White, & Hollins, 2008). In a study of 9891 deaths of people with IDD, the incidence of choking as a cause of death was 100 times greater than in the typically developed population (Dupont & Mortensen, 1998). Deaths from choking asphyxiation in adults increase with age (Berzlaovich, Fazeny-Dorner, Waldhoer, Fasching, & Keil, 2005). Pneumonia is a health care concern in the field of IDD for its associations with morbidity and mortality, health consequences, quality of life, and costs of care. Pneumonia and other respiratory diseases are the most common causes of death in adults with IDD in large residential care and small group home or community settings. A high proportion of pneumonia-related deaths occur among those with severe and profound IDD (Chadwick & Jolliffe, 2009; Durvasula, Beange, & Baker, 2009; Glover & Ayub, 2010; Heslop et al., 2013; Janicki, Dalton, Henderson, & Davidson, 2009). Additionally, non-fatal episodes of choking and pneumonia have a high incidence within this group (Beange, Lennox, & Parmenter, 2009; Dupont & Mortensen, 1998). In a community survey, more than 40% of responding caregivers for adults with developmental disabilities (DD) reported episodes of non-fatal choking episodes (NFCE) (Thacker et al., 2008). Given the risks of choking and pneumonia for adults with IDD, we argue that development of tools to identify risk indicators/factors that detect reliably those at high risk for these life-threatening conditions is critical. Such tools facilitate timely introduction of strategies to mitigate the risk. 1.2. Risk indicators for choking and pneumonia In order to identify risk indicators for choking and pneumonia, we reviewed the literature relating to physiological and behavioral factors associated with choking and pneumonia in individuals with IDD. Where research studies were absent, we referred to data in the general population of older people, as their cluster of impairments including physiologic, medical, cognitive and psychologic impairments that characterize aging have similarities to the lifelong impairments of adults with IDD (Deb, Thomas, & Bright, 2001; Janicki et al., 2009; Sheppard, 2010a). 1.2.1. Risk indicators associated with choking NFCEs, defined as “bolus misdirection into the airway” that require assistance to clear, were studied in a cohort of 75 patients with typical development or adult onset disorders (Ekberg & Feinberg, 1998). Choking occurred under varied conditions: on all solid food consistencies and liquids, during all meals and snacks, and in a variety of eating environments. The significant risk factors associated with choking were: being elderly, having a neurogenic condition, being dependent for feeding, and requiring special dysphagia diets. Anatomical or functional swallowing abnormalities (i.e., dysphagia) were noted on subsequent instrumental testing in some subjects (Ekberg & Feinberg, 1998). Thacker et al. (2008) used a caregiver survey to explore indicators of choking risk in adults with IDD and found in excess of 40% of respondents reported their cared ones had one or more NFCEs that occurred variably on food consistencies and on non-food items. Odds for choking were higher for individuals taking two or more medications, especially if they used tranquilizers. A cluster of “unable to read” (reflecting severity of intellectual impairment), “teeth condition” (cavities and poor oral hygiene), “medication use”, 62

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“use of tranquilizers” and “needing help with liquids” predicted choking for 62.1% of individuals (Thacker et al., 2008). Samuels and Chadwick (2006) examined factors associated with high risk of choking in adults with IDD and dysphagia using speech-language pathologist (SLP) surveys of eating patterns and videofluoroscopic swallowing assessments. Results revealed that eating characterized by increased speed of eating and ‘cramming’ (i.e., a large bolus or multiple boluses overloading the mouth) had significant association with SLPs’ judgment of high risk for choking. The cluster of ‘speed’ and ‘cramming’ plus premature loss of bolus into the pharynx as identified on videofluoscopic swallowing studies accurately differentiated 43.5% of the individuals judged by SLPs as low risk and 93% of the individuals judged as high risk for choking (Samuels & Chadwick, 2006). 1.2.2. Risk indicators associated with pneumonia Langmore et al. studied predictors for pneumonia in a mixed population of geriatric in- and out-patients and nursing home residents in prospective (Langmore et al., 1998) and retrospective (Langmore, Skarupski, Park, & Fries, 2002) studies. In the prospective study the best predictors of the occurrence of pneumonia were (a) dependence for feeding, (b) dependence for oral care, (c) number of decayed teeth, (d) tube feeding, (e) two or more medical diagnoses, (f) multiple medications and (g) smoking. In addition, factors associated with pneumonia were (a) chronic obstructive pulmonary disease (COPD), (b) congestive heart failure (CHF), (c) gastrointestinal (GI) disease, (d) presence of dysphagia and/or aspiration as seen on an instrumental examination of swallowing and (e) dry mouth or excessive oral secretions. The authors suggested that a cluster of risk indicators was needed to achieve a sensitive prediction of pneumonia (Langmore et al., 1998). The subsequent retrospective study of the nursing home population identified three variables that were significant in both studies. These were dependence for eating, presence of a feeding tube, and multiple medications. Additional predictors identified in the nursing home population were age, weight loss, and urinary tract infection (Langmore et al., 2002). The association between pneumonia and poor oral status has also been supported in a prospective study of individuals with IDD (Binkley, Haugh, Kitchens, Wallace, & Sessler, 2009). Finally, oropharyngeal and esophageal dysphagia and gastroesophageal reflux were associated with aspiration in children and adults with IDD (Arvedson, Rogers, Buck, Smart, & Msall, 1994; Rogers, Arvedson, Buck, Smart, & Msall, 1994; Rogers, Stratton et al., 1994). 1.3. Risk assessment in medical management Identifying risk indicators for disabling health conditions and initiating strategies to mitigate the risk for developing these conditions have been standards for health management (Buijsse, Simmons, Griffin, & Schulze, 2011; Scott, Votova, Scanlan, & Close, 2007; Wilson et al., 1998). Thus, there is a precedent for applying risk management for choking and pneumonia to adults with IDD. Differentiating between individuals who are at low or high risk for choking and pneumonia would aid in developing person centered interventions that may mitigate risk for those at high risk while avoiding increasing responsibility of care and initiating unnecessary lifestyle restrictions for individuals whose risk is low (Balandin, Hemsley, Sheppard, & Hanley, 2009; Thacker et al., 2008). Therefore, the purpose of this study was to develop and validate two assessments, the Choking Risk Assessment (CRA) and the Pneumonia Risk Assessment (PRA) that would differentiate adults with IDD at high risk for choking and for pneumonia from those at low risk. 2. Material and methods This study was approved by the Teachers College, Columbia University Institutional Review Board and by the data collection sites. The tests were adopted into the care plan for residents at the two centers and administered under a general consent signed by their guardians that allowed for clinical assessments and treatments. 2.1. Development of the assessments This study was conducted in three phases.

• Phase 1. Selection of risk factors/items to be used in the assessments. • Phase 2. Retrospective chart reviews to identify those adults with IDD in the study cohort who had experienced NFCEs and those in the cohort who had experienced non-fatal pneumonia episodes (NFPEs). • Phase 3. Administration of the CRA and PRA to the study cohorts to determine the psychometric properties of the assessments for differentiating those individuals who had experienced choking and pneumonia (those at high risk) from those who had not (those at low risk).

2.1.1. Selection of assessment risk factors/items Literature searches were conducted by the first author to identify factors associated with risk for pneumonia and risk for choking. An impairment framework consisting of physiologic and behavioral factors was used as the model for selecting test items (Sheppard, 2006; Sheppard, 2010a, 2010b; Stucki, Cieza, & Melvin, 2007). Population terms used for both searches were various combinations and permutations of: “adult”, “disability”, “developmental disability”, “geriatric”, “intellectual disability” or “learning disability” paired with condition terms. The condition terms for choking were “dysphagia”, “asphyxiation”, “choking”, “airway obstruction”; and for pneumonia were “dysphagia”, “aspiration”, “aspiration pneumonia” and “pneumonia”. The search engines, Medline Plus, Pubmed, Psychnet, PsychINFO, and CINHAL, yielded papers on behavioral and physiological risks that were associated with choking and with pneumonia in adults and children with DD and in typically developed geriatric populations. Based on the search, two 63

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preliminary lists with behavioral and physiological risk factors were created. In developing a list of test items, the preliminary lists of factors formed the basis for discussion in three focus groups, one at each of the two study sites and a third at an additional residential site for individuals with severe and profound IDD. Each of the groups consisted of the first author and at least one: SLP, occupational therapist or physical therapist, nurse, registered dietician, and residential care worker. All focus group participants were senior staff with a minimum of five years employment. In addition, behavioral specialists, physicians and psychologists participated in the discussions, according to their interest and availability. Criteria for final inclusion of test items were (a) prevalence in adults with IDD across multiple diagnoses, and (b) readily accessible clinical information in both in- and out-patient settings. Each of the risk factors identified in the literature were considered along with any additional factors derived from discussants’ clinical experience. During the first round of meetings within group consensus was reached on the potential items for inclusion in the CRA and PRA. Results were compiled and discussed at a second round of meetings for final selection of items. The number of items was limited to 10 for optimum efficiency and ease of completion of the assessment in terms of time. Percentage scoring was selected by the focus groups for its familiarity and ease of use, with 10% allotted for each item giving a total score for the 10 items of 100%. 2.1.2. Choking Risk Assessment items The risk factors included in the CRA were (a) age 40 years and older; (b) diagnosis of dysphagia; (c) history of coughing at meals and/or choking requiring assistance to clear; (d) medications associated with side or main effects of reduced alertness, reduced muscle tone, dry mouth or tardive dyskinesia syndrome; (e) mealtime actions (including food ‘stealing’, lability and mania); (f) mealtime behaviors (including distractibility, lethargy); (g) inadequate chewing ability for the diet consistency; (h) rapid rate of eating; (i) excessive bite size and (j) any one of a cluster of four risks that the focus groups considered clinically relevant: (1) difficulties with postural alignment for sitting, (2) PICA diagnosis, (3) rapid breathing during eating, and (4) recurring seizures (See Appendix A for CRA test form and User’s Guide criteria for scoring each item). 2.1.3. Pneumonia Risk Assessment items The risk factors included in the PRA were (a) age 40 years and older; (b) diagnosis of dysphagia with pharyngeal phase symptoms; (c) history of pneumonia; (d) poor oral/dental status; (e) dependent for oral care; (f) dependent for feeding or fed by tube; (g) multiple medical diagnoses and/or polypharmacy; (h) history of smoking; (i) dry mouth or excessive saliva; and (j) any one of a cluster of medical risks, including gastrointestinal, cardiac and pulmonary diagnoses (See Appendix B for PRA test form and User’s Guide criteria for scoring each item). 2.2. Phase 2. Study cohorts and chart reviews The cohorts consisted of convenience samples of adults with severe or profound IDD residing at two sites, Site A (n = 347) and Site B (n = 271). Nursing staff from both sites conducted retrospective chart reviews of the previous 5-years to search for NFCE incident reports. In addition, Site B nursing staff searched the charts for NFPE incident reports. Operational definitions for choking and pneumonia were provided to the chart reviewers to assure consistency. Choking as used in this study was defined as Levels 3, 4, or 5 on the Choking Staging Scale developed for this project (Sheppard, 2002a) (See Table 1). Level 3, corresponded to an occurrence of choking that required assistance with use of a suction machine, abdominal thrusts, or finger probes to rescue the individual from asphyxiation. Levels 4 and 5 described nursing care or hospitalization following the incident. Staff charted incident reports for all choking incidents that required assistance for rescue. These reports contained detailed descriptions of staff actions at the time of the choking incident and subsequent management. Pneumonia was defined as a charted occurrence of illness with a diagnosis of pneumonia signed by a medical doctor and confirmed by medical tests. Residents were assigned to group(s) based on their chart referenced history for choking and pneumonia: (1) a positive choking group (PCG), (2) a negative choking group (NCG), (3) a positive pneumonia group (PPG), and (4) a negative pneumonia group (NPG). Resident details were de-identified by using numbers as labels for the data. 2.3. Phase 3. Validity testing for the CRA and PRA Both site A and B adopted the CRA as part of their care plan. In addition, administration and staff at Site B adopted the PRA as part of their care plan and participated in the validation study for the PRA. All residents at Site A and Site B who were 25 years or older Table 1 Choking staging scale. Level

Description

1 2 3 4 5

Coughing during meals, snack, or on saliva Prolonged coughing cleared without assistance Procedure needed to clear the obstruction − suction, Heimlich, finger sweeps Emergency Care needed Hospitalization for pulmonary consequences

Sheppard (2002a).

64

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and had resided at the site for a minimum of 5 years were tested with the CRA (n = 619). Residents at Site B, meeting the same criteria, were also tested with the PRA (n = 271). Nursing staff provided the chart reviews for history of choking and pneumonia. SLPs, occupational therapists, and/or nurses who had not been involved in the chart reviews were assigned at random to administer the CRA and PRA. The staff who tested the residents with the CRA and the PRA were blinded to the results of the nursing reviews. In addition, as part of their routine clinical care residents had been tested annually by their assigned SLPs with the Dysphagia Disorder Survey (DDS) and the Dysphagia Management Staging Scale (DMSS) (Sheppard 2002b; Sheppard, Hochman, & Baer, 2014). The results from the most recent testing were used to answer the dysphagia diagnosis items on the risk assessments. The DDS and DMSS are standardized and validated clinical assessments that were developed for individuals with IDD and include signs and symptoms that are associated with impairment in the three phases of swallowing: pre-oral/oral, oral-pharyngeal and esophageal. The SLPs had been trained in the administration and scoring of the DDS and DMSS. Participating staff were familiar with the User’s Guides for the CRA and PRA and experienced with adults with IDD. Data for the CRA and PRA were subjected to statistical assessments for reliability and validity using Chronbach’s Coefficient Alpha, bivariate analysis and logistic regression. 3. Results 3.1. Choking Risk Assessment validation Of the 619 study participants, 93 (15.02%) were identified as having had choking incidents. This positive choking group (PCG) was compared to the remaining participants, the negative choking group (NCG). The CRA was assessed for internal consistency reliability using Cronbach’s coefficient alpha. The Cronbach’s alpha for the 10-item scale resulted in an α = 0.65, indicating a moderate level of internal consistency. In addition, bivariate analyses were conducted for the nine items that assessed the relationships between predictor variables and choking. Because all variables were dichotomized, cross-tabulations were used to assess relationships and these are presented in Table 2. Five of nine items were significantly associated with the history of choking. These were: (a) dysphagia diagnosis; (b) mealtime actions (labile, food stealing and/or mania), (c) reduced chewing ability and being on chewable diet; (d) rapid rate of eating for solids and/or liquids; and (e) excessive size mouthfuls for solids and/or liquids. The cluster of nine items was significantly related to choking occurrence (p < 0.001). The next step in the validity analysis was to run a logistic regression of the nine predictor variables on choking. Table 3 contains the results of the logistic regression analysis. The Nagelerke pseudo-r2 = 0.373 equation predicted a significant portion of variance in choking risk (χ2 = 148.12, 10 df, p < 0.001). Data reported in Table 3 indicate that the lack of a dysphagia diagnosis reduced the probability of choking by nearly half (Exp[B] = 0.503), as did the item “engaging in excessive mouthfuls of food” (Exp[B] = 0.513). Because the distribution of the sample of 619 subjects on the observed choking variable was 84.9% with a negative score or a score of less than 3 on the Choking Staging Scale, and 15.02% with a score of 3, 4 or 5, a cutoff point of 15% (score equivalent = 20%) was selected. By selecting a cutoff point approximating the sample distribution on the observed variable, false negatives were minimized. The assessment correctly predicted 85.8% of the sample. The specificity coefficient was 0.91 and the sensitivity coefficient was 0.53. Although the proportion of false positives was 49.5%, false negatives were 8.0%, meaning that 92.0% of those who had been diagnosed as having choking problems were correctly classified by the predictor variables on the choking indicator. Table 4 presents the cross-tabulation comparing observed versus predicted classifications. The final step in the validation process was to classify subjects who were in the PCG (high risk of choking) and those in the NCG (low risk for choking) on percentile rankings. Fig. 1 presents the cumulative distribution of the PCG and the NCG by percentile rankings. The NCG sample is clustered in the lower percentiles, whereas the PCG sample is clustered in the upper percentiles. These findings suggest that the CRA is a valid and useful instrument for diagnosis of choking probability using a 20% score cutoff. Although its sensitivity could be improved, CRA is quite accurate in identifying persons with a high probability of choking. 3.2. Pneumonia Risk Assessment validation Of the 271 study participants in the PRA part of the study, 44 (16.2%) were diagnosed with pneumonia during the previous five years according to the chart reviews. This positive pneumonia group (PPG) was compared to the negative pneumonia group (NPG) (n = 227). The PRA was first assessed on the PPG for internal consistency reliability using Cronbach’s coefficient alpha. The 10-item scale achieved an alpha of α = 0.73. The nine predictor variables were cross-tabulated with the incidence of pneumonia. The results of these analyses are presented in Table 5. The bivariate cross-tabulations indicate that 8 out of the 9 predictors were significantly related to the incidence of pneumonia in the previous five years. As seen in Table 5, these factors were, (a) patients 40 years old or older, (b) diagnosed with dysphagia, (c) required assisted feeding, (d) necessitated assistant oral care, (e) poor oral or dental status, (f) multiple medical diagnoses, (g) dry mouth or excess oral secretions, and (h) diseases and conditions. The cluster of nine items was significantly related to pneumonia occurrence (p < 0.001). The next step in the validity process was to regress the incidence of pneumonia on the nine predictors using a logistic regression. Results of the logistic regression analysis are presented in Table 6. The predictor variables set accounted for 32% of the variance in pneumonia incidents over the previous five years, which was statistically significant (Nagelkerke R2 = 0.320, χ2 = 56.573, 9 df, p < 0.001). The only significant independent predictor was 65

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Table 2 Bivariate relationships between predictor variables and incidence of choking in previous 5 years. History of Choking Risk factor

No

Yes

Total

Age < 40 n %

225 42.5

32 34.0

257 41.3

n %

304 57.5

62 66.0

366 58.7

χ2

df

p-value

2.37

1

0.12

12.09

1

0.00*

0.01

1

0.91

7.60

1

0.01*

0.96

1

0.33

9.02

1

0.00*

4.64

1

0.03*

12.18

1

0.00*

3.66

1

0.06

40+

Dysphagia Diagnosis No n %

193 36.5

17 18.1

210 33.7

n %

336 63.5

77 81.9

413 66.3

Yes

Medication No n %

71 13.4

13 13.8

84 13.5

n %

458 86.6

81 86.2

539 86.5

Yes

Mealtime Actions No n %

364 68.8

51 54.3

415 66.6

n %

165 31.2

43 45.7

208 33.4

Yes

Mealtime Behaviors No n %

370 69.9

61 64.9

431 69.2

n %

159 30.1

33 30.5

192 30.8

Yes

Reduced chewing ability No n %

350 66.2

47 50.0

397 63.7

n %

179 33.8

47 50.0

226 36.3

Yes

Rate of eating Normal n %

271 51.4

37 39.4

309 49.6

n %

257 48.6

57 60.6

314 50.4

Rapid

Excessive mouthfuls No n %

231 43.7

23 24.5

254 40.8

n %

298 56.3

71 75.5

369 59.2

Yes

Other problems No n %

382 72.5

59 62.8

441 71.0

n %

145 27.5

35 37.2

180 29.0

Yes

* p < 0.05

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Table 3 Summary of contributions of predictor variables to choking risk. Variable

B

S.E.

Wald

df

p-value

Exp(B)

Age Dysphagia Diagnosis Medication Mealtime Actions Mealtime Behaviors Reduced Chewing Ability Rate of eating Excessive Mouthfuls Other

0.011 −0.687 0.257 −0.360 0.146 −0.232 0.031 −0.667 −0.238

0.258 0.339 0.340 0.249 0.265 0.256 0.273 0.305 0.258

0.002 4.099 0.569 2.087 0.302 0.820 0.013 4.786 0.854

1 1 1 1 1 1 1 1 1

0.966 0.043* 0.451 0.149 0.582 0.365 0.911 0.029* 0.355

1.011 0.503 1.293 0.697 1.157 0.793 1.031 0.513 0.788

* p < 0.05 Table 4 Distribution of observed and predicted cases of choking in the previous 5 years. Predicted 3+ Choking Score Observed

No Yes Total

No

Yes

Total

% Correct

484 46 530

42 47 89

526 93 619

92.0 50.5 85.8

Fig. 1. Graphic representation of the distributions of choking and no choking samples on choking probability.

clinical diagnosis of dysphagia (Wald = 12.430, 1 df, p < 0.001). The absence of the diagnosis of dysphagia reduced the probability of pneumonia by 81% (Exp[B] = 0.191). Because the distribution of the sample of 271 subjects on the observed pneumonia variable was 83.76% in the NPG and 16.2% in the PPG, a cutoff point of 15% (score equivalent = 20%) approximated the sample distribution and minimized the false negatives. The assessment correctly predicted 76.8% of the sample. The sensitivity coefficient was 0.63 and the specificity coefficient was 0.92. Using the 15% cut-off point, the proportion of false positives was 25.4%, false negatives were 13.5%; meaning that 86.5% of those who had been diagnosed with pneumonia were correctly classified by the predictor variables on the pneumonia indicator. Table 7 presents the cross-tabulation comparing observed versus predicted classifications. On the basis of the summed scores on the risk factors, patients were ranked on percentiles. The distributions were dichotomized to compare the PPG and NPG. Twenty-two percent of the NPG are below the 20th percentile or below on the risk factors, while only 1% of the PPG are below the 20th percentile. The data in graphic form is in Fig. 2. As can be seen the NPG is at the lower levels of the distribution, while the PPG is at the higher levels.

4. Discussion 4.1. Overview of results Managing respiratory risks associated with swallowing in adults with IDD is challenging for both disability and health service 67

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Table 5 Bivariate relationships between predictor variables and incidence of pneumonia in previous 5 years. Pneumonia Predictor

No

Yes

Total

Age < 40 n %

111 48.7

12 27.3

123 45.2

n %

117 51.3

32 72.7

149 54.8

n %

209 91.7

21 47.7

230 84.6

n %

19 8.3

23 52.3

42 15.4

n %

153 67.1

21 47.7

174 64.0

n %

75 32.9

23 52.3

98 36.0

χ2

df

p-value

6.83

1

0.01*

54.54

1

0.00*

6.01

1

0.01*

17.78

1

0.00*

38.73

1

0.00*

5.85

1

0.02*

3.01

1

0.08

8.43

1

0.00*

8.89

1

0.00*

40+

Dysphagia No Yes

Feeding modality Oral/independent Tube or dependent

Assisted oral care No

Yes

n % n %

150 65.8

14 31.8

164 60.3

78 34.2

30 68.2

108 39.7

Poor oral/dental status No n %

212 93.0

26 59.1

238 87.5

n %

16 7.0

18 40.9

34 12.5

Yes

Multiple medical diagnoses No

Yes

n % n %

52 22.8 176 77.2

3 6.8 41 93.2

55 20.2 217 79.8

Tobacco use No n %

213 93.8

38 86.4

251 92.6

n %

14 6.2

6 13.6

20 7.4

Yes

Excess oral secretions No

Yes

n % n %

127 55.7 101 44.3

14 31.8 30 68.2

141 51.8 131 48.2

Gastro or pulmonary disease No n %

170 74.6

23 52.3

193 71.0

n %

58 25.4

21 47.7

79 29.0

n %

227 83.8

44 16.2

271 100.0

Yes

Total

* p < 0.05

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Table 6 Summary of contributions of predictor variables to pneumonia risk. Predictor

B

S.E.

Wald

df

Sig.

Exp(B)

Age > 40 Dysphagia Poor dental status Oral care dependent Dependent feeder Multiple diagnoses/prescriptions Smoker Dry mouth or excess oral secretions GI, GER, CHF, COPD, asthma, esophageal dysmotility

0.000 −1.655 0.818 −1.058 −1.018 −0.632 −1.279 −0.366 −0.188

0.441 0.469 0.570 0.574 0.625 0.686 0.680 0.466 0.417

0.000 12.430 2.057 3.405 2.652 0.851 3.543 0.616 0.204

1 1 1 1 1 1 1 1 1

0.999 0.000* 0.152 0.065 0.103 0.356 0.060 0.432 0.652

1.000 0.191 2.265 0.347 0.361 0.531 0.278 0.694 0.828

* p < 0.01. Table 7 Distribution of observed and predicted cases of pneumonia in the previous 5 years. Pneumonia past 5 years

Predicted

Observed

No

Yes

Total

% Correct

No Yes Total

180 16 196

47 28 75

227 44 271

79.3 63.4 76.8

Fig. 2. Graphic representation of the distributions of pneumonia and no pneumonia samples on pneumonia probability.

providers. The combination of physiologic, behavioral, and developmental impairments that impact swallowing functions directly are compounded by high prevalence of gastrointestinal, cardiac and respiratory disorders, long term polypharmacy, difficulties with communication, and dependence on caregivers for recognizing their particular needs (Chadwick & Jolliffe, 2009; Chadwick, Jolifffe, Goldbart, & Burton, 2006; Leslie, Crawford, & Wilkinson, 2009; Matson, Fodstad & Boisjoli, 2008; Sheppard, 2002, 2010a). Adults with IDD are a heterogeneous population with a range of ability and disability. This study provides insight into choking and pneumonia and the potential for differentiating individuals with severe and profound IDD at high or low risk for both these health issues. Our aim was to develop and validate assessments for discriminating between adults at high or low risk for choking and pneumonia, and, thereby, inform the allocation of resources to those with higher probability of occurrence. Our results reveal that the CRA and PRA are valid and reliable tools for this purpose. Specifically, we found that five of the nine predictor variables on the CRA and eight of the nine predictor variables on the PRA were significantly related to observed choking and pneumonia. Furthermore, the use of the predictor variables significantly increased the accuracy of prediction relative to the a priori defined PCG, NCG, PPG and NPG. Using a 15% (score of 20%) cutoff point, the predictor variables correctly identified 92% of the choking group and 86.5% of the pneumonia group. The data suggest that the CRA and PRA have high specificity, and thus can be used successfully as predictors of choking and pneumonia in a sample of adults with IDD. 4.2. Clinical dysphagia evaluation In this study clinically diagnosed dysphagia was related significantly to history of choking and of pneumonia. The evaluations 69

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used to identify dysphagia, the DDS and DMSS (Sheppard et al., 2014), were developed specifically for this population of individuals with IDD. Although clinical evaluations are indirect observations of many of the signs and symptoms of dysphagia, these risk assessment tools have the advantage of being applicable to adults with IDD and medically and economically feasible. While instrumental evaluations of swallowing (i.e., videofluoroscopic swallowing study and nasopharyngeal endoscopy) are considered the gold standards for direct observation, the significant associations between the clinical diagnosis of dysphagia and history of choking and pneumonia indicate that the CRA and PRA may also be used as objective indicators for further evaluation for dysphagia and referral for an instrumental evaluation. 4.3. Approach to selection of assessment items The nature and severity of the outcome for choking and pneumonia episodes depend on a variety of factors that are situational, social, psychological, and diet-related, as well as physiologic and behavioral (Balandin et al., 2009; Harris, Baker, Smith, & Harris, 1984). In these assessments we have followed the approach of others in selecting physiologic and behavioral characteristics of the individual as predictors of risk (Samuels & Chadwick, 2006; Smith, Teo, & Simpson, 2014), in an effort to minimize the effect of variability of management on the resulting estimate of individual vulnerability. However, psychosocial and environmental factors are also important in the management of adults with IDD (Balandin et al., 2009; Guthrie & Stansfield, 2017; Matson et al., 2008; Matson & Kuhn, 2001; Thacker et al., 2008). Researchers have considered these factors in surveys of caregivers regarding choking (Guthrie & Stansfield, 2017; Thacker et al., 2008) and included them in assessments [e.g., The Screening Tool of Feeding Problems (STEP) (Matson et al., 2008), and the Nutrition and Swallowing Checklist (Stewart, 2003)]. The complexity of interacting factors related to choking and pneumonia risk are reflected in the comments made by adults with cerebral palsy whose choking and coughing during mealtimes and when taking medications were reported to increase with age (Balandin et al., 2009). Occurrences of choking and coughing were inconsistent and associated with food textures and viscosity, fatigue, distraction, talking during eating, and being rushed by care workers providing mealtime assistance. Balandin et al. (2009) reported that adults with cerebral palsy experienced choking events as frightening, humiliating and embarrassing, particularly when eating in public, as reflected in the following quotes: “I felt awful because everyone was staring at me. I had two staff members trying to get it down, I eventually won, but it was a real fight” (p. 200), and “Richard (65 years) said that he was “dreading” eating in public at work events due to his poor saliva control, recurrent coughing, and choking episodes that he found ‘humiliating’ and ‘embarrassing’ (p. 201). Participants also expressed concerns about pneumonia and related hospitalization (Balandin et al., 2009). In addition to causing such distress and mortality, pneumonia has been observed clinically to cause functional regression or deterioration in eating and swallowing, thereby reducing quality of life and increasing responsibilities in the care for the individual. These factors further highlight the importance for early identification and management of those individuals at high risk. 4.3.1. Age and risk of choking and pneumonia The onset age for risk of 40 years was selected for the age item on the CRA and PRA and resulted from focus group discussions. Although 40 years is younger than the age indicators in studies of swallowing related risks associated with aging in typically developed older individuals (Ney, Weiss, Kind, & Robbins, 2009; Robbins, Bridges, & Taylor, 2006) clinical observations as well as evidence in studies of adults with IDD suggested the lower age cutoff was appropriate (Balandin et al., 2009; Strauss, Anderson, Shavelle, Sheridan, & Trenkle, 1998). Our results supported the hypothesis that 40 years and older was appropriate as an independent predictor of pneumonia but not as an independent predictor for choking. In a study of changes in clinical signs of dysphagia with age, the average age for onset and increasing severity of signs and symptoms of dysphagia in adults with severe and profound IDD was 33.39 years old (Sheppard, 2002a). Mortality in this fourth decade was also noted by Strauss et al. (1998). They reported that the average age at death was 33.5 years in community residences and 36.7 years in institutional residences. In their study, pneumonia and other respiratory diseases were the most common causes of death (Strauss et al., 1998). In addition, although ages of 65 years and older have been associated with choking in the typically developed population (Boyd, Chatterjee, Chiles, & Chin, 2009; Ekberg & Feinberg, 1998), our results indicate that in populations with IDD choking may be associated with younger as well as older adults (Balandin et al., 2009; Ball et al., 2012). Further study on the contribution of age is needed as is study of the many issues related to clinical use of these risk assessments. In addition to adults mortality and morbidity associated with choking and pneumonia are a serious health care challenge in children with IDD (Arvedson et al., 1994; Harris et al., 1984; Heslop et al., 2013; Waltz & Katz, 2006). Assessments for predicting vulnerable children would be valuable additions to management. Research is needed, however, to determine the predictors of these risks and if the research model for the CRA and PRA would be applicable for the pediatric population of children with IDD. 5. Limitations In this study, the environment, diagnosis of IDD, medical and dietary management of the population were controlled incidentally by the residential status of the individuals and the diagnoses of severe and profound IDD. While this allowed us to better examine the relationship of the physiologic and behavioral variables for the occurrence of choking and pneumonia, it limits the applicability of the results to the wider population. The results, therefore, should be extrapolated to other populations with IDD with some caution. Further study on the effects of these variables is needed. In this study the risk events that identified the individuals in the PPG and the PCG had occurred over a five-year retrospective interval. Although it is logical to assume that history is relevant for predicting risk, prospective research is needed to study the 70

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predictive parameters of the tests. There are limitations related to the sample. Individuals who had experienced fatal choking and fatal pneumonia in the five-year retrospective interval were not included in this cohort. In addition, although staff was required to chart these events, the possibility does exist that incidents of choking and pneumonia may not have been reported. These factors and the aging of the study population prior to testing would indicate that this analysis of risk is a conservative one. Therefore, the score cutoff that minimizes false negatives should be considered most appropriate in scoring the CRA and PRA. Furthermore, restricting our data collection to non-fatal choking or pneumonia events may limit the applicability for predicting fatal episodes. To our knowledge, differences between variables associated with non-fatal and fatal choking and pneumonia have not been studied and, therefore, should not be assumed to be interchangeable but require further study. In consideration of these limitations and in summary we would iterate that there is a potential that these risk assessments might miss-represent an individual’s level of risk for NFCE and NFPE. 6. Conclusion Risk assessment is a well-accepted strategy for proactive medical intervention for a range of chronic and episodic disabling health conditions. It is formulated as a means of identifying risk and intervening with strategies selected to mitigate and potentially avoid the manifestation of the risk. Differentiating high and low risk individuals is the first step in risk management. Although risk indicators for non-fatal choking or pneumonia events have been studied for individuals with IDD, to our knowledge the CRA and PRA are the first assessments designed to differentiate high from low risk individuals with IDD and thereby predict their probability of occurrence of choking and pneumonia. Our results indicate that the CRA and the PRA are valid and reliable means to support risk management in adults with IDD. In addition, they are objective measures of risk that may be useful for testing hypotheses about the causes of choking and pneumonia in this population, for research on the effectiveness of interventions, and for educating caregivers about the vulnerability of their cared ones. Acknowledgements The authors express their sincere appreciation to the administrations, staff and residents of the Glenwood Resource Center, the Woodward Resource Center and the Woodbridge Developmental Center for their participation in this investigation. We also acknowledge with gratitude the contributions of Ralph Larkin for his expert guidance with the statistical analyses and Felicity Burke for her insightful editorial comments.

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Appendix A

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Appendix B

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