Elderly Health Journal

1. ASEAN Institute for Health Development, Mahidol University, Salaya, Phutthamonthon, Nakhon Pathom, Thailand
2. Department of Research Administration and Development, University of Limpopo, Polokwane, South Africa
3. Department of Psychology, College of Medical and Health Science, Asia University, Taichung, Taiwan

Introduction
 

Exposure variables
    Sociodemographic variables consisted of education (none and ≥ 1 years), age group (60 - 69, 70-79 and 80 or more years), sex (male, female), marital status (currently married vs. widowed / divorced/separated / deserted / live-in relationship / never married), residence (rural, urban) and receipt of health insurance. Social network was measured with 11 items, e.g., “Eat-out-of-house (restaurant/hotel)” (13). Responses were coded 1 = daily to at least once a month and 0 = rarely/once a year or never (Cronbach’s alpha 0.66).
    Food insecurity was sourced from four items, 1) “In the last 12 months, did you ever reduce the size of your meals or skip meals because there was not enough food at your household? (Yes/No), 2) In the last 12 months, were you hungry but didn’t eat because there was not enough food at your household? (Yes/No), 3). In the past 12 months, did you ever not eat for a whole day because there was not enough food at your household?, 4) Do you think that you have lost weight in the last 12 months because there was not enough food in your household?” (13). Any positive response to the four questions was scored as one.
Health status variables
    Self-rated health status was sourced from the question, “In general, would you say your health is excellent, very good, good, fair, or poor?” (13).

    Chronic conditions were sourced from the question, “Has any health professional ever told you that you have…?”: 1) “ Hypertension or high blood pressure (Yes/No); 2) Diabetes or high blood sugar; 3) Cancer or malignant tumor; 4) Chronic lung disease such as asthma, chronic obstructive pulmonary disease/chronic bronchitis or other chronic lung problems; 5) Chronic heart diseases such as coronary heart disease (heart attack or myocardial infarction), congestive heart failure, or other chronic heart problems; 6) Stroke; 7) Arthritis or rheumatism, Osteoporosis or other bone/joint diseases, and 8) High cholesterol (Yes/No).” (13). Summed responses were trichotomized into 0, 1, or 2 or more chronic conditions.

    Insomnia symptoms were assessed with four questions: (1) “How often do you have trouble falling asleep?” (2) “How often do you have trouble with waking up during the night?” (3) “How often do you have trouble with waking up too early and not being able to fall asleep again?” (4) “How often do you feel really rested when you wake up in the morning?”. Responses options were “never, rarely (1-2 nights per week), occasionally (3-4 nights per week), and frequently (5 or more nights per week)” (13). Insomnia symptoms were coded as “frequently” for the first three symptoms and “never or rarely” for the fourth symptom as one. Participants who reported any of these four symptoms were classified as having sleep problems (17).
    Major depressive disorder (MDD) in the past 12 months was assessed with the Health and Retirement Study (HRS) Composite International Diagnostic Interview Short Form (CIDI-SF) (18), using criteria of the Diagnostic and Statistical Manual of Mental Disorders (DSM); American Psychiatric Association (19). Study respondents were required to “endorse either anhedonia or depressed mood for most of the day for most of a 2-week period or more,” and those who fulfilled this criterion “completed an additional seven symptoms: lost interest, feeling tired, change in weight, trouble with sleep, trouble concentrating, feeling down, and thoughts of death.” (20). “Those with a score ≥3 were considered to meet the criteria for having MDD in the previous 12 months; MDD symptomology scores ranged from 0 to 7.” (20).

    Anthropometry: “Height and weight of adults were measured using the Seca 803 digital scale.” (13). BMI was calculated according to Asian criteria: underweight (< 18.5 kg/m²), normal weight (18.5-22.9 kg/m²), overweight (23.0-24.9 kg/m²), class I obesity (25.0-29.9 kg/m²), and class II obesity (≥ 30.0 kg/m²)” (21).

    Physical pain was defined as “troubled by pain and required some form of medication or treatment for relief of pain.” (13).

    Vision was assessed with two questions, 1) “How good is your eyesight for seeing things at a distance, like recognizing a person across the street (or 20 meters away), whether or not you wear glasses, contacts, or corrective lenses?” and 2) “How good is your eyesight for seeing things up close, like reading an ordinary newspaper print whether or not you wear glasses, contacts, or corrective lenses?” (13). Response options ranged from very good (1) to very poor (5) and poor near or far vision as defined as “poor or very poor”

    Hearing problem was measured with the item. “Have you ever been diagnosed with any hearing or ear-related problem or condition?” (Yes/No) (13).
    Falls were assessed with the item, “How many times have you fallen in the last 2 years?” (number) (13).
    Vigorous physical activity. “For vigorous activity, respondents were asked about their involvement in running or jogging, swimming, going to a health centre/gym, cycling, digging with a spade or shovel, heavy lifting, chopping, farm work, fast bicycling, and cycling with loads.” (13). Responses were trichotomized into 1 = hardly ever/never, 2 = less than twice a week, and 3 = more than once a week (22).

    Verbal recall was based on memory functioning of a list of 10 words and defined as 7-10 words good, 4-7 words medium and 0-3 words poor (23).

 

Variable		Sample	≥ 1 difficulties in ADL*	≥ 1 difficulties in IADL*
		N (%)	%	%
Sociodemographic factors
All		31477	23.8	48.4
Age in years	60-69    70-79    80 or more	18979 (58.5) 9108 (30.2) 3390 (11.3)	17.7 27.9 44.1	40.9 55.1 69.5
Sex	Female    Male	16371 (52.5) 15106 (47.5)	26.4 20.9	56.9 38.8
Education	≥ 1 years    No schooling	14583 (43.5) 16894 (56.5)	20.6 26.2	37.4 56.7
Food insecurity	No    Yes	28355 (89.5) 2747 (10.5)	22.4 35.0	46.8 61.4
Marital status	Married Widowed/separated/never married	19926 (61.6) 11545 (38.4)	20.8 28.6	41.5 59.3
Residence	Rural    Urban	20730 (70.5) 10747 (29.5)	24.4 22.2	51.6 40.5
Social network	Low   Medium   High	13047 (44.4) 9096 (28.2) 8871 (27.4)	28.2 22.4 17.9	54.2 47.4 39.8
Has health insurance		6573 (18.2)	19.5	43.4
Health status	Self-rated health status (poor or fair)	14379 (48.6)	31.6	58.8
Chronic conditions	0    1    2 or more	14538 (47.3) 9306 (29.5) 7536 (23.2)	18.7 25.4 32.2	42.9 50.1 57.2
Insomnia symptoms		4357 (14.8)	36.7	61.9
Major depressive disorder		2029 (8.2)	40.9	66.7
Body mass index	Normal    Underweight    Overweight/obesity	10560 (37.9) 6524 (26.9) 10706 (35.3)	20.4 24.8 21.5	45.6 52.9 44.6
Physical pain		3858 (13.9)	36.6	63.8
Poor distant vision		6479 (21.2)	36.7	64.2
Poor near vision		6424 (20.7)	35.5	62.2
Hearing/ear problem		3155 (9.6)	33.3	63.8
Falls in past 2 years		3270 (12.6)	27.6	53.0
Vigorous physical activity	Hardly ever/never    ≤ Once a week    > Once a week	69.4 (68.9) 7.4 (7.8) 23.2 (23.3)	27.2 15.6 16.5	52.8 41.2 38.0
Word recall	Low (0-3)    Medium (4-6)    High (7-10)	7575 (25.6) 17917 (59.4) 4863 (14.9)	31.5 20.7 15.7	58.5 46.7 31.6

Variable		All (%)	Male (%)	Female (%)
ADL	Dressing	7.1	6.2	8.0
	Walking across a room	7.5	6.4	8.5
	Bathing	7.4	6.5	8.2
	Eating, difficulties	8.4	7.1	9.5
	Getting in or out of bed	12.1	10.2	13.8
	Using the toilet	17.5	15.4	19.4
IADL	Preparing a hot meal	18.4	16.4	20.3
	Shopping for groceries	23.7	17.8	28.9
	Making telephone calls	28.6	21.5	34.9
	Taking medications	15.7	11.5	19.4
	Doing work around the house or garden	26.5	20.5	31.9
	Managing money	27.6	17.5	36.7
	Getting around	29.8	19.3	39.1

Discussion
    In this nationally representative sample of older adults (≥ 60 years) in India in 2017-2019, the prevalence of ADL difficulty (23.8%), IADL difficulty (48.4%) and ADL/IADL difficulty (52.0 %), was higher than in Ireland (≥ 65 years, 13% ADL, 11% IADL, and 18% ADL/IADL) (3), in Southeastern Poland (≥ 60 years, 17.1% ADL and 35.8% IADL) (4), in China (≥ 60 years, 7.0% ADL/IADL disability) (5), in Brazil (≥ 60 years, 7.3% ADL and 17.3% IADL) (6), and in Malaysia (≥ 60 years, 17.0% ADL and 42.9% IADL) (7). Functional disability rates are also higher than in community dwellers in North India (≥ 60 years, 5.5% ADL and 21.8% IADL) (8), but lower than and among 246 persons in rural West Bengal (≥ 60 years, 32.4% ADL and 59.3% IADL) (9), and in the six low- and middle-income countries SAGE study (60-69 years, 27.7% vs 17.7% in this study) (2). This study confirms that ADL/IADL difficulties are significant issues in older Indians, calling for integrating geriatric assessment and care into primary care as well as increased social security measures (9, 24).
    While in a study in Northern India, bathing was the most difficult ADL task (20%) and transportation (32%) and shopping (29%) were the most difficult IADL task (8), in this study use of toilet was the most difficult ADL task (17.5), and transportation (getting around) (29.8%) and making telephone calls (28.6%) were the most difficult IADL tasks. In Ireland dressing (9%) was the most difficult ADL (3), while in this study dressing was the least difficult ADL (7.1%), and the most difficult IADL in Ireland was doing household chores (7%) (3), while in this study household or garden work (26.5%) was the fourth difficult IADL. Similarly to our study, in Brazil the two most difficult IADL were transfer (23.0%) and using the toilet (22.1%) (6).
    In line with previous research (increasing age (3, 8); female sex (1, 5), rural residence (5, 25), lower education (1, 26), this study showed that increasing age, female sex, lower education and rural residence were associated with ADL and/or IADL difficulty.
Possible reasons for the high prevalence of IADL in rural areas may be related to higher rates of no education (56.0% rural and 27.7% urban areas), poor verbal recall (20.6% vs. 11.5%), poor distant vision (15.5% vs 10.0%), food insecurity (9.5% vs. 5.6%) and major depressive disorder (6.9% in rural and 4.7% in urban areas). Receipt of health insurance and in univariate analysis social network were protective against ADL and IADL difficulty, which is consistent with previous research (social contacts) (4). It is of importance to increase membership of health insurance and to facilitate older person’s social participation to strengthen their psychophysical condition (4).
    Consistent with previous research (poor self-rated health (8), chronic condition (3), pain (3), poor or fair self-rated health and chronic conditions, physical pain, poor distant and near vision were associated with both ADL and IADL difficulty, and hearing or ear problems were associated with IADL difficulty. It is possible that as a result pain, poor self-rated health status, and chronic conditions older adults are limited in performing ADL and/or IADL (8). Exercise and pain and chronic disease management may reduce some of the functional disability (3, 8).
    The study found a positive association between insomnia symptoms, MDD, and ADL and IADL difficulty, which is consistent with previous research findings (9, 12), including a longitudinal study (27). However, it is also possible that the relationship between insomnia symptoms, MDD, and functional disability is bidirectional (3).
    Nevertheless, early diagnosis and management of sleep and depressive disorders are indicated to reduce their effects (3). In agreement with former investigations (6), falls were in univariate analysis found to increase the odds of ADL and IADL difficulty. In addition, poor memory function was associated with ADL and IADL difficulty which is consistent with former investigations (3). Screening of cognitive status may be indicated to delay the process of disability (3).
 

Variable		ADL 1 plus		IADL 1 plus
		CrOR (95% CI)	AOR (95% CI)	CrOR (95% CI)	AOR (95% CI)
Sociodemographic factors
Age in years	60-69    70-79    80 or more	1 (Reference) 1.80 (1.61, 2.01)*** 3.66 (3.14, 4.26)***	1 (Reference) 1.56 (1.36, 1.80)*** 2.22 (1.78, 2.76)***	1 (Reference) 1.78 (1.60, 1.97)*** 3.29 (2.81, 3.87)***	1 (Reference) 1.45 (1.28, 1.63)*** 2.23 (1.74, 2.86)***
Sex	Female    Male	1 (Reference) 0.74 (0.67, 0.82)***	1 (Reference) 0.86 (0.74, 0.99)*	1 (Reference) 0.48 (0.44, 0.53)***	1 (Reference) 0.62 (0.55, 0.70)***
No education (base: some)		1.37 (1.24, 1.52)***	0.97 (0.83, 1.13)	2.20 (1.98, 2.44)***	1.56 (1.38, 1.77)***
Food insecurity		1.87 (1.63, 2.14)***	1.56 (1.30, 1.88)***	1.80 (1.59, 2.05)***	1.33 (1.14, 1.56)***
Marital status	Widowed/separated/never married    Married	1 (Reference) 0.65 (0.59, 0.73)***	1 (Reference) 0.97 (0.84, 1.11)	1 (Reference) 0.49 (0.44, 0.53)***	1 (Reference) 0.77 (0.68, 0.88)***
Residence	Rural    Urban	1 (Reference) 0.88 (0.78, 1.00)	1 (Reference) 0.91 (0.78, 1.07)	1 (Reference) 0.64 (0.56, 0.73)***	1 (Reference) 0.68 (0.60, 0.77)***
Social network	Low    Medium    High	1 (Reference) 0.74 (0.66, 0.82)*** 0.56 (0.48, 0.65)***	1 (Reference) 0.99 (0.87, 1.13) 0.94 (0.79, 1.12)	1 (Reference) 0.76 (0.70, 0.83)*** 0.56 (0.48, 0.65)***	1 (Reference) 1.06 (0.95, 1.18) 0.98 (0.84, 1.13)
Has health insurance		0.74 (0.65, 0.84)***	0.75 (0.65, 0.96)***	0.78 (0.71, 0.86)***	0.83 (0.74, 0.94)**
Health status
Self-rated health status (poor or fair)		2.71 (2.41, 3.04) ***	1.78 (1.06, 2.03)***	2.43 (2.21, 2.68)***	1.80 (1.60, 2.02)***
Chronic conditions	0    1    2 or more	1 (Reference) 1.48 (1.31, 1.67)*** 2.07 (1.81, 2.37)***	1 (Reference) 1.17 (1.01, 1.35)* 1.66 (1.41, 1.89)***	1 (Reference) 1.34 (1.22, 1.47)*** 1.77 (1.56, 2.02)***	1 (Reference) 1.21 (1.07, 1.35)** 1.70 (1.48, 1.96)***
Insomnia symptoms		2.11 (1.90, 2.36)***	1.40 (1.22, 1.61)***	1.91 (1.72, 2.11)***	1.32 (1.16, 1.50)***
Major depressive disorder		2.56 (2.21, 2.97)***	1.48 (1.20, 1.83)***	2.36 (2.03, 2.74)***	1.38, 1.15, 1.66)***
Body mass index	Normal    Underweight    Overweight/obesity	1 (Reference) 1.29 (1.14, 1.46)*** 1.07 (0.93, 1.22)	1 (Reference) 1.14 (0.98, 1.31) 1.06 (0.92, 1.25)	1 (Reference) 1.34 (1.21, 1.48)*** 0.96 (0.85, 1.09)	1 (Reference) 1.13 (1.00, 1.27)* 1.02 (0.90, 1.15)
Physical pain		2.08 (1.85, 2.34)***	1.63 (1.41, 1.89)***	2.08 (1.86, 2.33)***	1.60 (1.39, 1.84)***
Poor distant vision		2.28 (2.05, 2.54)***	1.30 (1.13, 1.50)***	2.27 (2.05, 2.51)***	1.23 (1.08, 1.40)**
Poor near vision		2.11 (1.89, 2.35)***	1.24 (1.07, 1.43)**	2.03 (1.83, 2.24)***	1.23 (1.07, 1.40)**
Hearing/ear problem		1.70 (1.40, 2.06)***	1.16 (0.91, 1.46)	2.01 (1.68, 2.40)***	1.40 (1.18, 1.66)***
Falls in the past 2 years		1.38 (1.55, 1.57)***	1.13 (0.98, 1.31)	1.33 (1.19, 1.49)***	1.03 (0.90, 1.17)
Vigorous physical activity	Hardly ever/never    ≤Once a week    >Once a week	1 (Reference) 0.50 (0.40, 0.62)*** 0.53 (0.46, 0.61)***	1 (Reference) 0.76 (0.56, 1.04) 0.88 (0.76, 1.03)	1 (Reference) 0.63 (0.54, 0.73)*** 0.55 (0.49, 0.61)***	1 (Reference) 0.90 (0.74, 1.10) 0.90 (0.80, 1.02)
Word recall	High (7-10)    Medium (4-6)    Low (0-3)	1 (Reference) 1.41 (1,21, 1.63)*** 2.47 (2.12, 2.89)***	1 (Reference) 1.14 (0.96, 1.35) 1.60 (1.31, 1.95)***	1 (Reference) 1.90 (1.68, 2.14)*** 3.06 (2.70, 3.46)***	1 (Reference) 1.42 (1.23, 1.64)*** 1.67 (1.42, 1.96)***

    Participation in vigorous physical activity was found in univariate analysis protective against ADL and IADL difficulty, which is consistent with previous research (3, 4), and shows the importance of promoting physical activity. In line with previous research (26), this study showed that being married was protective against IADL difficulty, and underweight increased the odds of IADL difficulty, which is consistent with some former research (28).
 
Conclusions
    Almost one in four older adults in India had ADL difficulty and almost half had IADL difficulty. Sociodemographic factors (older age, female sex, no education, food insecurity and rural residence), and health status factors (poor or fair self-rated health status, chronic conditions, insomnia symptoms, major depressive disorder, physical pain, poor distant vision, poor near vision, hearing or ear problems, underweight and poor word recall) were identified for ADL and/or IADL difficulty, which can be utilized in targeting interventions.
 
Study limitations
    The study was limited by its cross-sectional design and the self-report of most data collected. Some variables, such as barriers and obstacles in the environment (4), were not assessed in this study but since they influence functional disability, should be included in future research. Since this study only included community-dwelling older adults, persons under institutional care were excluded, the prevalence of functional disability may have been underestimated.
 
Acknowledgements
    "The Longitudinal Aging Study in India Project is funded by the Ministry of Health and Family Welfare, Government of India, the National Institute on Aging (R01 AG042778, R01 AG030153), and United Nations Population Fund, India."
 
Availability of data and materials
    “The data are available at the Gateway to Global Aging Data (www.g2aging.org).”
 
Conflict of interests
    The authors declare that they have no competing interests.
 
Authors’ contributions
    “All authors fulfill the criteria for authorship. SP and KP conceived and designed the research, performed statistical analysis, drafted the manuscript, and made critical revisions of the manuscript for key intellectual content. All authors read and approved the final version of the manuscript and have agreed to the authorship and order of authorship for this manuscript.”
 
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