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Does glucose tolerance affect quality of life in an elderly population?
Diabetes Research and Clinical Practice 46 (1999) 161 – 167 www.elsevier.com/locate/diabres
Does glucose tolerance affect quality of life in an elderly population? Liisa Hiltunen a,b,*, Sirkka Keina¨nen-Kiukaanniemi a,b a
Department of Public Health Science and General Practice, Uni6ersity of Oulu, PO Box 5000, FIN-90401 Oulu, Finland b Oulu Uni6ersity Hospital, Kajaanintie 50, 90220 Oulu, Finland Received 15 March 1999; received in revised form 30 April 1999; accepted 29 June 1999
Abstract The aim of the present study was to describe the associations between glucose tolerance and quality of life in an unselected non-institutionalised elderly population aged 73 years or over (n= 259, of whom 93 were men). Diabetes was assessed on the basis of self-reports and 2-h oral glucose tolerance tests (1985 WHO criteria). Quality of life was evaluated with the Nottingham Health Profile instrument (NHP). A greater proportion of the previously diagnosed diabetic patients reported to have problems on all the three energy items, on nearly all the physical mobility items and on half of the pain items compared to the subjects with undiagnosed diabetes, impaired glucose tolerance or normal glucose tolerance. The results of the second part of the NHP were in line with those of the first part, showing that more of the persons with previously diagnosed diabetes had problems on the following items: jobs around the house, hobbies and holidays compared to the other study groups. As for the six quality of life dimensions in the first part of the NHP, the previously diagnosed diabetic persons scored clearly higher on the energy, pain and physical mobility dimensions of the NHP compared to all the other subjects. To conclude, elderly subjects with previously diagnosed diabetes had a poorer quality of life compared to those with undiagnosed diabetes, impaired glucose tolerance or normal glucose tolerance. © 1999 Elsevier Science Ireland Ltd. All rights reserved. Keywords: Elderly; Glucose tolerance; Diabetes; Quality of life
1. Introduction Diabetes is a common chronic disease, and its prevalence increases remarkably upon ageing [1 – 5]. According to the current guidelines, one of the main treatment objectives for type 2 diabetic persons is to retain their quality of life as good as * Corresponding author.
possible [6]. The results of the previous studies on diabetic patients quality of life (QOL) are difficult to compare because they involve many methodological and other differences, e.g. focus on varying age or patients groups and/or have a limited perspective towards quality of life, such as treatment satisfaction [7–13]. The findings have varied from study to study [7–13], but some studies have shown type 2 diabetes to have a major impact on
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the patients’ perceived quality of life [11 – 13]. Elderly diabetic patients have not been included in most studies, and there is a lack of data on the impact of undiagnosed diabetes or impaired glucose tolerance on elderly subjects’ quality of life. The aim of this study was to evaluate elderly subjects’ quality of life in different glucose tolerance categories with the Nottingham Health Profile (NHP) instrument [14].
2. Subjects and methods The study population consisted of communityliving persons born in 1920 or earlier and resident on 1 September, 1991, in three small municipalities (Kempele, Oulunsalo, Hailuoto) in northern Finland. In 1994–1995 these subjects also participated in the follow-up of a baseline study conducted in 1991–1992 [15]. The study population was examined between 1 October, 1994 and 4 May, 1995, and the examination included a 2-h oral glucose tolerance test (OGTT) and a measurement of quality of life by the Nottingham Health Profile questionnaire [14 – 16]. The presence of diabetes mellitus was assessed by questions of the participants’ previously diagnosed diabetes and by an OGTT. All the participants except the diabetic patients on oral hypoglycaemic drug or insulin treatment underwent an oral glucose tolerance test which was performed and classified according to the current WHO criteria [17]. The NHP questionnaire was sent to all the eligible participants two weeks before the examination date. The questionnaire was checked at the time of the examination together with an examination assistant, who helped to fill in the missing points when necessary. The NHP questionnaire is divided into two parts. The first part consists of 38 statements concerning health problems, which make up six QOL dimensions: energy (three statements), sleep (five statements), pain (eight statements), emotional reactions (nine statements), social isolation (five statements) and physical mobility (eight statements). The second part consists of seven statements measuring the effects of the health problems on paid employment, jobs
around the house, social life, home life, sex life, hobbies and holidays. The respondent is instructed to answer ‘yes’ if the statement corresponds to his/her present state and ‘no’ if it is not true. The first item of the second part of the NHP on paid employment was excluded, because all of these elderly subjects were retired. The dimensions of the first part of the NHP have a theoretical sum score of 100. This assignment is done separately in each user country, so that the results reflect the values of the ‘general population’. Then ‘yes’ answers are summed up for each dimension; if the respondent has only ‘no’ answers on a given dimension, he/she scores an index value of 0, while ‘yes’ answers on all the items of a given dimension result in an index value of 100. OGTT: Capillary blood samples were obtained before and 2 h after a 75 g glucose load (75 g glucose in 300 ml water, or Glucodyn, Leiras) in the morning (between 7.30 and 9.30). The maximum deviation allowed for the 2-h blood sample was 5 min. The blood glucose measurements were determined daily from capillary whole blood using a glucosedehydrogenase (anhydrous glucose) enzymatic method (Merck Glucose System 250, FRG, Darmstadt). The coefficients of variation (CVs) for within-run studies were 0.4–1.6% when the corresponding blood glucose values were 3.3 mmol/l and 18.0 mmol/l. For day-to-day studies the CV was 1.6% on the upper end of the reference range. A person was classified as having previously diagnosed diabetes if he/she was on oral drug or insulin treatment or if he/she was on diet treatment and in addition the OGTT 2-h value was E 11.1 mmol/l. A person without previously diagnosed diabetes was classified as having previously undiagnosed diabetes if the 2-h OGTT was E 11.1 mmol/l and impaired glucose tolerance (IGT) with a 2-h value of 7.8 to 11.0 mmol/l. Those with 2-h OGTT valuesB 7.8 mmol/l were classified as having normal glucose tolerance (NGT).
2.1. Statistical methods The results of the individual NHP items were presented as the proportions of ‘yes’ replies with
L. Hiltunen, S. Keina¨nen-Kiukaanniemi / Diabetes Research and Clinical Practice 46 (1999) 161–167
age and gender adjustment. The index values for the six different NHP dimensions were also calculated separately for each glucose tolerance category according to gender. Since the study was an observational survey without random sampling, no P-values were used to assess the role of chance variation [18].
3. Results 79% (n=259, of whom 92 were men) out of the eligible 327 (112 men) subjects took part in the study in 1994–1995. The median age of the participating men was 77 years (range 75 – 94) and that of the women 79 years (range 73 – 96).
3.1. Glucose tolerance status 15% (n=14) of the men were diagnosed as having previously diagnosed diabetes, 8% (n = 7) as having previously undiagnosed diabetes, 36% (n= 33) as having IGT and the remaining 41% (n = 38) as having normal glucose tolerance. The corresponding figures for the women were: 22% (n = 37), 8% (n=13), 37% (n =61) and 34% (n = 56), respectively.
3.2. Indi6idual NHP items The age- and gender -adjusted proportions of ‘yes’ replies on the items of the NHP are presented in Table 1. A greater proportion of the previously diagnosed diabetic patients reported problems on all the three energy items compared with the NGT group, and the result was almost similar compared with the other study groups. On half of the pain items, more of them also replied ‘yes’ than the other study subjects. Apart from one item (I am unable to walk at all), a greater proportion of the previously diagnosed diabetic patients reported problems in physical mobility compared with the subjects with undiagnosed diabetes, IGT or NGT. In addition, a smaller proportion of the previously undiagnosed diabetic patients reported problems in some of the pain and physical mobility items compared with the other study groups. However, the relatively small
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number of participants in this group may have affected these results. As for emotional reactions, the result was similar on three out of nine items, and on one out of the five sleep items (I lie awake for most of the night), but the proportion of ‘yes’ replies did not differ between the study groups on the social isolation items. The proportion of persons replying ‘yes’ on the items of the second part of the NHP was greater for half of the six items (jobs around the house, hobbies, holidays) among the previously diagnosed diabetic persons compared with the other study groups.
3.3. Results of the six quality of life dimensions of the NHP questionnaire The previously diagnosed diabetic persons scored clearly higher on the energy, pain and physical mobility dimensions of the NHP compared with all the other study groups (Table 2). 4. Discussion Though the participation rate was moderately high (79%) among this elderly population with a median age of 78 years, the relatively small number of participants in each glucose tolerance group prevents any far-reaching generalisation of the results. One standardised way of measuring quality of life is to use questionnaires. The NHP has welldocumented reliability and validity and is useful in describing the impact of chronic disease on patients’ quality of life [19]. However, the oldest age groups were excluded from most of the validation studies. The 2-h glucose tolerance tests were performed in accordance with the current WHO criteria, which have been generally accepted for epidemiological purposes [17]. However, previous studies have shown that the reproducibility of OGTT is poor even over a short interval, and the marked intraindividual variability of 2-h OGTT has been shown among both middle-aged and elderly populations [20–22]. Thus, the OGTT results could have varied if the OGTT had been repeated.
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Table 1 The percentage distribution (numbers in parentheses) of the study subjects who replied ‘yes’ to the NHP questions by glucose tolerance category and adjusted for age and gendera NHP Item
Energy I’m tired all the time Everything is an effort I soon run out of energy Sleep I take tablets to help me sleep I lie awake for most of the night I sleep badly at night It takes me a long time to get sleep I’m waking up in the early hours of the morning
Prev. DM (n =51)
Undg. DM (n =20)
IGT (n =94)
NGT (n =94)
34 (17) 53 (27) 63 (32)
23 (5) 11 (2) 34 (6)
20 (19) 23 (21) 33 (31)
18 (16) 28 (25) 31 (28)
33 29 35 33
25 13 25 39
29 10 28 27
38 17 33 37
(17) (14) (17) (17)
(5) (3) (5) (8)
(28) (9) (27) (26)
(34) (16) (30) (33)
55 (27)
55 (11)
63 (59)
59 (55)
Pain I have unbearable pain I’m in constant pain I have pain at night I’m in pain when I walk I’m in pain when I’m sitting I find it painful to change position I’m in pain when I’m standing I’m in pain when going up and down stairs or steps
23 24 30 53 19 20 38 55
(12) (13) (14) (27) (9) (10) (20) (26)
4 12 14 28 13 15 11 27
(1) (3) (3) (6) (2) (3) (2) (5)
7 11 21 35 7 20 18 34
(7) (11) (20) (32) (7) (18) (17) (31)
7 17 33 34 16 19 24 30
(7) (14) (31) (31) (15) (18) (22) (28)
Emotional reactions I feel that life is not worth living Worry is keeping me awake at night I feel as I’m losing control I have forgotten what its like to enjoy myself I wake up feeling depressed Things are getting me down I’m feeling on edge I lose my temper easily these days The days seem to drag
7 24 18 23 6 42 12 8 8
(4) (11) (8) (11) (3) (21) (6) (4) (5)
15 22 6 5 10 23 17 7 9
(3) (4) (1) (1) (2) (5) (3) (2) (2)
11 13 8 22 5 30 10 12 20
(11) (12) (8) (20) (6) (28) (9) (10) (18)
14 18 4 12 10 28 8 5 15
(11) (17) (4) (12) (8) (25) (8) (5) (13)
Social isolation I feel there is nobody I’m close to I’m finding it hard to get on with people I feel I’m a burden to people I’m finding it hard to make contact with people I feel lonely
3 2 8 7 25
(3) (1) (5) (4) (11)
5 6 6 5 4
(2) (1) (2) (1) (1)
2 3 13 6 24
(3) (3) (13) (6) (24)
7 2 15 9 23
(5) (2) (11) (8) (21)
Physical mobility I’m unable to walk at all I can only walk about indoors I find it hard to dress myself I have trouble getting up and down stairs or steps I need help to walk about outside I find it hard to stand for long I find it hard to bend I find it hard to reach for things
0 10 28 68 67 72 60 72
(0) (6) (15) (34) (34) (36) (30) (36)
0 0 3 35 15 40 15 24
(0) (0) (1) (7) (2) (8) (3) (5)
0 2 12 42 27 50 29 37
(1) (3) (10) (39) (27) (47) (28) (35)
0 2 13 36 31 41 30 35
(0) (2) (11) (32) (27) (37) (27) (31)
L. Hiltunen, S. Keina¨nen-Kiukaanniemi / Diabetes Research and Clinical Practice 46 (1999) 161–167
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Table 1 (Continued) NHP Item
Part II Jobs around the house Social life Home life Sex life Hobbies Holidays
Prev. DM (n = 51)
Undg. DM (n =20)
IGT (n =94)
NGT (n =94)
81 44 17 12 76 65
44 30 17 33 44 45
49 32 11 18 39 44
50 30 9 11 44 31
(41) (22) (9) (6) (37) (32)
(9) (6) (3) (4) (9) (9)
(47) (31) (10) (12) (37) (42)
(45) (26) (8) (10) (39) (28)
a Prev. DM, previously diagnosed diabetes; Undg. DM, undiagnosed diabetes; IGT, impaired glucose tolerance; NGT, normal glucose tolerance.
Table 2 Mean index values of the six NHP dimensions and proportions (% n) of subjects scoring more than zero in the six NHP dimensions by glucose tolerance category and in the total study populationa
Energy Sleep Pain Emotion Social isolation Physical mobility
Mean Score\0 Mean Score\0 Mean Score\0 Mean Score\0 Mean Score\0 Mean Score\0
Prev. DM
Undg. DM
IGT
NGT
Total
(n= 51)
(n =20)
(n = 94)
(n = 94)
(n =259)
47 73 34 71 30 80 17 58 9 32 37 92
23 42 27 74 11 33 13 26 7 21 13 47
25 44 26 78 16 50 14 54 10 33 20 71
23 40 32 80 21 54 12 47 9 32 17 60
28 48 30 77 20 56 14 50 9 32 22 70
(37) (36) (39) (28) (16) (47)
(8) (14) (6) (5) (4) (9)
(41) (73) (46) (49) (30) (67)
(37) (74) (50) (43) (30) (55)
(123) (197) (141) (125) (80) (178)
a Prev. DM, previously diagnosed diabetes; Undg. DM, undiagnosed diabetes; IGT, impaired glucose tolerance; NGT, normal glucose tolerance.
Quality of life is a multidimensional phenomenon, which includes physical, psychological and social well being. In almost all these aspects and in line with some previous studies [13,23], the previously diagnosed elderly diabetic patients’ quality of life was poorer compared to the other study subjects and they scored higher on all the energy items, on most of the pain items, on all of the physical mobility items, on one out of the five sleep items, and on some of the emotion items compared to the other study groups. The finding that the undiagnosed dia-
betic patients reported less problems in some of the pain and physical mobility items might be due to several reasons; eg. less rapidly progressing complications, less physical disabilities as well as a better overall health compared with the previously diagnosed diabetic patients. The results of the second part of the NHP, where the previously diagnosed diabetic patients scored higher than the other groups on the items of ‘jobs around the house’, ‘hobbies’ and ‘holidays’, were congruent with those of the first part.
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However, there were no differences in social isolation between the study groups, and only a few differences emerged on most of the sleep and emotional reaction items. Whether and to what extent this is due to the diagnosis itself or the treatment (diet, health behaviour changes) or complications that affect elderly diabetic patients’ quality of life is unclear. Since a great proportion of the diabetic patients already have complications at the time of diagnosis, it is possible that the diagnosis itself and the associated label of being diabetic in addition to the necessary modifications in lifestyle and the regular drug treatment may contribute to the patients’ perceived quality of life [24]. The role of complications may be more pronounced on the pain and physical mobility items and can be associated with such conditions as neuropathy and atherosclerotic complications. In addition, some other causes, such as a poorer overall physical health, higher number of other concomitant diseases other than those related to diabetes could explain this finding. To sum up, previously diagnosed elderly diabetic patients’ quality of life was inferior to that of subjects with undiagnosed diabetes, IGT or NGT. This finding suggests that the diabetic label, the generally recommended changes in lifestyle or the treatment as well as the development of long-term complications may all contribute negatively to elderly diabetic patients’ perceived quality of life. Some of these factors are possibly modifiable, and the elderly diabetic patients’ quality of life might be improved by altering them.
References [1] M.I. Harris, W. Hadden, W. Knowler, P. Bennet, Prevalence of diabetes and impaired glucose tolerance and plasma glucose levels in U.S. population aged 20–74 years, Diabetes 36 (1987) 523–534. [2] J. Mc Phillips, E. Barrett-Connor, D. Wingard, Cardiovascular disease risk factors prior to the diagnosis of impaired glucose tolerance and non-insulin dependent diabetes mellitus in a community of older adults, Am. J. Epidemiol. 131 (1990) 443–452. [3] L. Mykka¨nen, M. Laakso, M. Uusitupa, K. Pyo¨ra¨la¨,
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the oral glucose tolerance test: a pilot study, Clin. Chem. 36 (1990) 125 – 128. [23] S. Keina¨nen-Kiukaanniemi, A. Ohinmaa, H. Pajunpa¨a¨, P. Koivukangas, Health related quality of life in diabetic patients measured by the Nottingham Health Profile, Diabetic Med. 13 (1996) 382 – 388. [24] A. Ruigomez, L. Garcia Rodriguez, Presence of diabetes related complication at the time of NIDDM diagnosis: an important prognostic factor, Eur. J. Epidemiol. 14 (1998) 439 – 445.
Does glucose tolerance affect quality of life in an elderly population? Liisa Hiltunen a,b,*, Sirkka Keina¨nen-Kiukaanniemi a,b a
Department of Public Health Science and General Practice, Uni6ersity of Oulu, PO Box 5000, FIN-90401 Oulu, Finland b Oulu Uni6ersity Hospital, Kajaanintie 50, 90220 Oulu, Finland Received 15 March 1999; received in revised form 30 April 1999; accepted 29 June 1999
Abstract The aim of the present study was to describe the associations between glucose tolerance and quality of life in an unselected non-institutionalised elderly population aged 73 years or over (n= 259, of whom 93 were men). Diabetes was assessed on the basis of self-reports and 2-h oral glucose tolerance tests (1985 WHO criteria). Quality of life was evaluated with the Nottingham Health Profile instrument (NHP). A greater proportion of the previously diagnosed diabetic patients reported to have problems on all the three energy items, on nearly all the physical mobility items and on half of the pain items compared to the subjects with undiagnosed diabetes, impaired glucose tolerance or normal glucose tolerance. The results of the second part of the NHP were in line with those of the first part, showing that more of the persons with previously diagnosed diabetes had problems on the following items: jobs around the house, hobbies and holidays compared to the other study groups. As for the six quality of life dimensions in the first part of the NHP, the previously diagnosed diabetic persons scored clearly higher on the energy, pain and physical mobility dimensions of the NHP compared to all the other subjects. To conclude, elderly subjects with previously diagnosed diabetes had a poorer quality of life compared to those with undiagnosed diabetes, impaired glucose tolerance or normal glucose tolerance. © 1999 Elsevier Science Ireland Ltd. All rights reserved. Keywords: Elderly; Glucose tolerance; Diabetes; Quality of life
1. Introduction Diabetes is a common chronic disease, and its prevalence increases remarkably upon ageing [1 – 5]. According to the current guidelines, one of the main treatment objectives for type 2 diabetic persons is to retain their quality of life as good as * Corresponding author.
possible [6]. The results of the previous studies on diabetic patients quality of life (QOL) are difficult to compare because they involve many methodological and other differences, e.g. focus on varying age or patients groups and/or have a limited perspective towards quality of life, such as treatment satisfaction [7–13]. The findings have varied from study to study [7–13], but some studies have shown type 2 diabetes to have a major impact on
0168-8227/99/$ - see front matter © 1999 Elsevier Science Ireland Ltd. All rights reserved. PII: S 0 1 6 8 - 8 2 2 7 ( 9 9 ) 0 0 0 8 2 - 0
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L. Hiltunen, S. Keina¨nen-Kiukaanniemi / Diabetes Research and Clinical Practice 46 (1999) 161–167
the patients’ perceived quality of life [11 – 13]. Elderly diabetic patients have not been included in most studies, and there is a lack of data on the impact of undiagnosed diabetes or impaired glucose tolerance on elderly subjects’ quality of life. The aim of this study was to evaluate elderly subjects’ quality of life in different glucose tolerance categories with the Nottingham Health Profile (NHP) instrument [14].
2. Subjects and methods The study population consisted of communityliving persons born in 1920 or earlier and resident on 1 September, 1991, in three small municipalities (Kempele, Oulunsalo, Hailuoto) in northern Finland. In 1994–1995 these subjects also participated in the follow-up of a baseline study conducted in 1991–1992 [15]. The study population was examined between 1 October, 1994 and 4 May, 1995, and the examination included a 2-h oral glucose tolerance test (OGTT) and a measurement of quality of life by the Nottingham Health Profile questionnaire [14 – 16]. The presence of diabetes mellitus was assessed by questions of the participants’ previously diagnosed diabetes and by an OGTT. All the participants except the diabetic patients on oral hypoglycaemic drug or insulin treatment underwent an oral glucose tolerance test which was performed and classified according to the current WHO criteria [17]. The NHP questionnaire was sent to all the eligible participants two weeks before the examination date. The questionnaire was checked at the time of the examination together with an examination assistant, who helped to fill in the missing points when necessary. The NHP questionnaire is divided into two parts. The first part consists of 38 statements concerning health problems, which make up six QOL dimensions: energy (three statements), sleep (five statements), pain (eight statements), emotional reactions (nine statements), social isolation (five statements) and physical mobility (eight statements). The second part consists of seven statements measuring the effects of the health problems on paid employment, jobs
around the house, social life, home life, sex life, hobbies and holidays. The respondent is instructed to answer ‘yes’ if the statement corresponds to his/her present state and ‘no’ if it is not true. The first item of the second part of the NHP on paid employment was excluded, because all of these elderly subjects were retired. The dimensions of the first part of the NHP have a theoretical sum score of 100. This assignment is done separately in each user country, so that the results reflect the values of the ‘general population’. Then ‘yes’ answers are summed up for each dimension; if the respondent has only ‘no’ answers on a given dimension, he/she scores an index value of 0, while ‘yes’ answers on all the items of a given dimension result in an index value of 100. OGTT: Capillary blood samples were obtained before and 2 h after a 75 g glucose load (75 g glucose in 300 ml water, or Glucodyn, Leiras) in the morning (between 7.30 and 9.30). The maximum deviation allowed for the 2-h blood sample was 5 min. The blood glucose measurements were determined daily from capillary whole blood using a glucosedehydrogenase (anhydrous glucose) enzymatic method (Merck Glucose System 250, FRG, Darmstadt). The coefficients of variation (CVs) for within-run studies were 0.4–1.6% when the corresponding blood glucose values were 3.3 mmol/l and 18.0 mmol/l. For day-to-day studies the CV was 1.6% on the upper end of the reference range. A person was classified as having previously diagnosed diabetes if he/she was on oral drug or insulin treatment or if he/she was on diet treatment and in addition the OGTT 2-h value was E 11.1 mmol/l. A person without previously diagnosed diabetes was classified as having previously undiagnosed diabetes if the 2-h OGTT was E 11.1 mmol/l and impaired glucose tolerance (IGT) with a 2-h value of 7.8 to 11.0 mmol/l. Those with 2-h OGTT valuesB 7.8 mmol/l were classified as having normal glucose tolerance (NGT).
2.1. Statistical methods The results of the individual NHP items were presented as the proportions of ‘yes’ replies with
L. Hiltunen, S. Keina¨nen-Kiukaanniemi / Diabetes Research and Clinical Practice 46 (1999) 161–167
age and gender adjustment. The index values for the six different NHP dimensions were also calculated separately for each glucose tolerance category according to gender. Since the study was an observational survey without random sampling, no P-values were used to assess the role of chance variation [18].
3. Results 79% (n=259, of whom 92 were men) out of the eligible 327 (112 men) subjects took part in the study in 1994–1995. The median age of the participating men was 77 years (range 75 – 94) and that of the women 79 years (range 73 – 96).
3.1. Glucose tolerance status 15% (n=14) of the men were diagnosed as having previously diagnosed diabetes, 8% (n = 7) as having previously undiagnosed diabetes, 36% (n= 33) as having IGT and the remaining 41% (n = 38) as having normal glucose tolerance. The corresponding figures for the women were: 22% (n = 37), 8% (n=13), 37% (n =61) and 34% (n = 56), respectively.
3.2. Indi6idual NHP items The age- and gender -adjusted proportions of ‘yes’ replies on the items of the NHP are presented in Table 1. A greater proportion of the previously diagnosed diabetic patients reported problems on all the three energy items compared with the NGT group, and the result was almost similar compared with the other study groups. On half of the pain items, more of them also replied ‘yes’ than the other study subjects. Apart from one item (I am unable to walk at all), a greater proportion of the previously diagnosed diabetic patients reported problems in physical mobility compared with the subjects with undiagnosed diabetes, IGT or NGT. In addition, a smaller proportion of the previously undiagnosed diabetic patients reported problems in some of the pain and physical mobility items compared with the other study groups. However, the relatively small
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number of participants in this group may have affected these results. As for emotional reactions, the result was similar on three out of nine items, and on one out of the five sleep items (I lie awake for most of the night), but the proportion of ‘yes’ replies did not differ between the study groups on the social isolation items. The proportion of persons replying ‘yes’ on the items of the second part of the NHP was greater for half of the six items (jobs around the house, hobbies, holidays) among the previously diagnosed diabetic persons compared with the other study groups.
3.3. Results of the six quality of life dimensions of the NHP questionnaire The previously diagnosed diabetic persons scored clearly higher on the energy, pain and physical mobility dimensions of the NHP compared with all the other study groups (Table 2). 4. Discussion Though the participation rate was moderately high (79%) among this elderly population with a median age of 78 years, the relatively small number of participants in each glucose tolerance group prevents any far-reaching generalisation of the results. One standardised way of measuring quality of life is to use questionnaires. The NHP has welldocumented reliability and validity and is useful in describing the impact of chronic disease on patients’ quality of life [19]. However, the oldest age groups were excluded from most of the validation studies. The 2-h glucose tolerance tests were performed in accordance with the current WHO criteria, which have been generally accepted for epidemiological purposes [17]. However, previous studies have shown that the reproducibility of OGTT is poor even over a short interval, and the marked intraindividual variability of 2-h OGTT has been shown among both middle-aged and elderly populations [20–22]. Thus, the OGTT results could have varied if the OGTT had been repeated.
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Table 1 The percentage distribution (numbers in parentheses) of the study subjects who replied ‘yes’ to the NHP questions by glucose tolerance category and adjusted for age and gendera NHP Item
Energy I’m tired all the time Everything is an effort I soon run out of energy Sleep I take tablets to help me sleep I lie awake for most of the night I sleep badly at night It takes me a long time to get sleep I’m waking up in the early hours of the morning
Prev. DM (n =51)
Undg. DM (n =20)
IGT (n =94)
NGT (n =94)
34 (17) 53 (27) 63 (32)
23 (5) 11 (2) 34 (6)
20 (19) 23 (21) 33 (31)
18 (16) 28 (25) 31 (28)
33 29 35 33
25 13 25 39
29 10 28 27
38 17 33 37
(17) (14) (17) (17)
(5) (3) (5) (8)
(28) (9) (27) (26)
(34) (16) (30) (33)
55 (27)
55 (11)
63 (59)
59 (55)
Pain I have unbearable pain I’m in constant pain I have pain at night I’m in pain when I walk I’m in pain when I’m sitting I find it painful to change position I’m in pain when I’m standing I’m in pain when going up and down stairs or steps
23 24 30 53 19 20 38 55
(12) (13) (14) (27) (9) (10) (20) (26)
4 12 14 28 13 15 11 27
(1) (3) (3) (6) (2) (3) (2) (5)
7 11 21 35 7 20 18 34
(7) (11) (20) (32) (7) (18) (17) (31)
7 17 33 34 16 19 24 30
(7) (14) (31) (31) (15) (18) (22) (28)
Emotional reactions I feel that life is not worth living Worry is keeping me awake at night I feel as I’m losing control I have forgotten what its like to enjoy myself I wake up feeling depressed Things are getting me down I’m feeling on edge I lose my temper easily these days The days seem to drag
7 24 18 23 6 42 12 8 8
(4) (11) (8) (11) (3) (21) (6) (4) (5)
15 22 6 5 10 23 17 7 9
(3) (4) (1) (1) (2) (5) (3) (2) (2)
11 13 8 22 5 30 10 12 20
(11) (12) (8) (20) (6) (28) (9) (10) (18)
14 18 4 12 10 28 8 5 15
(11) (17) (4) (12) (8) (25) (8) (5) (13)
Social isolation I feel there is nobody I’m close to I’m finding it hard to get on with people I feel I’m a burden to people I’m finding it hard to make contact with people I feel lonely
3 2 8 7 25
(3) (1) (5) (4) (11)
5 6 6 5 4
(2) (1) (2) (1) (1)
2 3 13 6 24
(3) (3) (13) (6) (24)
7 2 15 9 23
(5) (2) (11) (8) (21)
Physical mobility I’m unable to walk at all I can only walk about indoors I find it hard to dress myself I have trouble getting up and down stairs or steps I need help to walk about outside I find it hard to stand for long I find it hard to bend I find it hard to reach for things
0 10 28 68 67 72 60 72
(0) (6) (15) (34) (34) (36) (30) (36)
0 0 3 35 15 40 15 24
(0) (0) (1) (7) (2) (8) (3) (5)
0 2 12 42 27 50 29 37
(1) (3) (10) (39) (27) (47) (28) (35)
0 2 13 36 31 41 30 35
(0) (2) (11) (32) (27) (37) (27) (31)
L. Hiltunen, S. Keina¨nen-Kiukaanniemi / Diabetes Research and Clinical Practice 46 (1999) 161–167
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Table 1 (Continued) NHP Item
Part II Jobs around the house Social life Home life Sex life Hobbies Holidays
Prev. DM (n = 51)
Undg. DM (n =20)
IGT (n =94)
NGT (n =94)
81 44 17 12 76 65
44 30 17 33 44 45
49 32 11 18 39 44
50 30 9 11 44 31
(41) (22) (9) (6) (37) (32)
(9) (6) (3) (4) (9) (9)
(47) (31) (10) (12) (37) (42)
(45) (26) (8) (10) (39) (28)
a Prev. DM, previously diagnosed diabetes; Undg. DM, undiagnosed diabetes; IGT, impaired glucose tolerance; NGT, normal glucose tolerance.
Table 2 Mean index values of the six NHP dimensions and proportions (% n) of subjects scoring more than zero in the six NHP dimensions by glucose tolerance category and in the total study populationa
Energy Sleep Pain Emotion Social isolation Physical mobility
Mean Score\0 Mean Score\0 Mean Score\0 Mean Score\0 Mean Score\0 Mean Score\0
Prev. DM
Undg. DM
IGT
NGT
Total
(n= 51)
(n =20)
(n = 94)
(n = 94)
(n =259)
47 73 34 71 30 80 17 58 9 32 37 92
23 42 27 74 11 33 13 26 7 21 13 47
25 44 26 78 16 50 14 54 10 33 20 71
23 40 32 80 21 54 12 47 9 32 17 60
28 48 30 77 20 56 14 50 9 32 22 70
(37) (36) (39) (28) (16) (47)
(8) (14) (6) (5) (4) (9)
(41) (73) (46) (49) (30) (67)
(37) (74) (50) (43) (30) (55)
(123) (197) (141) (125) (80) (178)
a Prev. DM, previously diagnosed diabetes; Undg. DM, undiagnosed diabetes; IGT, impaired glucose tolerance; NGT, normal glucose tolerance.
Quality of life is a multidimensional phenomenon, which includes physical, psychological and social well being. In almost all these aspects and in line with some previous studies [13,23], the previously diagnosed elderly diabetic patients’ quality of life was poorer compared to the other study subjects and they scored higher on all the energy items, on most of the pain items, on all of the physical mobility items, on one out of the five sleep items, and on some of the emotion items compared to the other study groups. The finding that the undiagnosed dia-
betic patients reported less problems in some of the pain and physical mobility items might be due to several reasons; eg. less rapidly progressing complications, less physical disabilities as well as a better overall health compared with the previously diagnosed diabetic patients. The results of the second part of the NHP, where the previously diagnosed diabetic patients scored higher than the other groups on the items of ‘jobs around the house’, ‘hobbies’ and ‘holidays’, were congruent with those of the first part.
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However, there were no differences in social isolation between the study groups, and only a few differences emerged on most of the sleep and emotional reaction items. Whether and to what extent this is due to the diagnosis itself or the treatment (diet, health behaviour changes) or complications that affect elderly diabetic patients’ quality of life is unclear. Since a great proportion of the diabetic patients already have complications at the time of diagnosis, it is possible that the diagnosis itself and the associated label of being diabetic in addition to the necessary modifications in lifestyle and the regular drug treatment may contribute to the patients’ perceived quality of life [24]. The role of complications may be more pronounced on the pain and physical mobility items and can be associated with such conditions as neuropathy and atherosclerotic complications. In addition, some other causes, such as a poorer overall physical health, higher number of other concomitant diseases other than those related to diabetes could explain this finding. To sum up, previously diagnosed elderly diabetic patients’ quality of life was inferior to that of subjects with undiagnosed diabetes, IGT or NGT. This finding suggests that the diabetic label, the generally recommended changes in lifestyle or the treatment as well as the development of long-term complications may all contribute negatively to elderly diabetic patients’ perceived quality of life. Some of these factors are possibly modifiable, and the elderly diabetic patients’ quality of life might be improved by altering them.
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