|
 
 |
| ORIGINAL ARTICLE |
|
| Year : 2021 | Volume
: 22
| Issue : 2 | Page : 139-147 |
|
Prevalence and correlates of insomnia symptoms among older adults in India: Results of a national survey in 2017-2018
Supa Pengpid1, Karl Peltzer2
1 Professor, ASEAN Institute for Health Development, Mahidol University, Salaya, Phutthamonthon, Nakhon Pathom, Thailand; Research Associate, Department of Research Administration and Development, University of Limpopo, Turfloop, South Africa
2 Research Associate, Department of Research Administration and Development, University of Limpopo, Turfloop, South Africa
| Date of Submission | 04-Mar-2021 |
| Date of Acceptance | 17-Mar-2021 |
| Date of Web Publication | 31-Aug-2021 |
Correspondence Address:
Prof. Karl Peltzer
Department of Research Administration and Development, University of Limpopo, Polokwane, Private Bag X1106, Sovenga 0727
South Africa
 Source of Support: None, Conflict of Interest: None
DOI: 10.4103/amh.amh_19_21
Background: This study aimed to estimate the prevalence and correlates of insomnia symptoms among older adults in India.
Methods: The study included 72,262 individuals (45 years and older) from the cross-sectional 2017 to 2018 Longitudinal Ageing Study in India Wave 1.
Results: The prevalence of insomnia symptoms was 12.7%, 13.2% among women and 11.9% among men. In the adjusted logistic regression analysis, food insecurity (adjusted odds ratio [AOR]: 1.41, 95% confidence interval [CI]: 1.25–1.59), feeling alone (AOR: 1.64, 95% CI: 1.46–1.83), having 3–5 discrimination experiences (AOR: 1.53, 95% CI: 1.32–1.78), having two or more chronic conditions (AOR: 1.65, 95% CI: 1.46–1.86), high functional disability (AOR: 1.80, 95% CI: 1.63–1.99), poor distant vision (AOR: 1.32, 95% CI: 1.17–1.49), poor near vision (AOR: 1.19, 95% CI: 1.07–1.33), edentulism (lost all teeth) (AOR: 1.28, 95% CI: 1.06–1.55), underweight (AOR: 1.11, 95% CI: 1.00–1.23), and pain (AOR: 1.71, 95% CI: 1.54–1.89) were positively associated with insomnia symptoms. High subjective socioeconomic status (AOR: 0.85, 95% CI: 0.76–0.96), urban residence (AOR: 0.90, 95% CI: 0.81–0.99), and medium social network (AOR: 0.87, 95% CI: 0.79–0.96) were negatively associated with insomnia symptoms.
Conclusions: More than one in ten older adults in India had insomnia symptoms and several associated factors were identified.
Keywords: India, insomnia, older adults
How to cite this article:
Pengpid S, Peltzer K. Prevalence and correlates of insomnia symptoms among older adults in India: Results of a national survey in 2017-2018. Arch Ment Health 2021;22:139-47 |
How to cite this URL:
Pengpid S, Peltzer K. Prevalence and correlates of insomnia symptoms among older adults in India: Results of a national survey in 2017-2018. Arch Ment Health [serial online] 2021 [cited 2022 Jun 26];22:139-47. Available from: https://www.amhonline.org/text.asp?2021/22/2/139/325046 |
| Introduction | |  |
Globally, among adults, 10%–15% report symptoms of insomnia associated with daytime consequences.[1] Among older adults, 36%–69% report sleep disturbances.[2] Insomnia symptoms and sleep disturbances impact negatively on quality of life, physical and mental morbidity and mortality.[3],[4],[5],[6] “Identifying specific factors which increase the risk of developing insomnia symptoms and sleep disturbances can help target interventions and in turn improve the overall health of our aging population.”[7]
In a national study among 50 years and older persons in India, the prevalence of severe or extreme sleep problems (single item measure) was 15.0% in 2007[8] and among 65 years and older 37.7%.[9] In a survey among grandparents of schoolchildren (n = 1240) in New Delhi, 10.3% had sleep disordered breathing and 14.3% had restless leg syndrome, and 8% were using sleeping pills.[10] In a community survey among older adults (n = 94, ≥60 years) in Mugalur village near Bangalore, 13.0% had insomnia.[11] Among attendants or relatives of hospital outpatients (n = 1050) in South India, the prevalence of insomnia was 18.6%,[12] and in accompanying relatives (n = 301) of hospital outpatients in Puducherry, India, the prevalence of poor sleep (Pittsburgh Sleep Quality Index score >5) was 39.2%.[13] In an urban household survey (n = 1185, mean age 44.5 years) in West Bengal, India, the prevalence of insomnia was 15.4% (based on the Insomnia Symptoms Questionnaire).[14] Of the respondents with insomnia in South India, “18% had difficulty in initiating sleep, 18% in maintaining sleep, and 7.9% had early morning awakening,” and health seeking was 0.3%.[12] There is a lack of recent studies estimating the national prevalence and correlates of insomnia symptoms among older adults in India.
Factors associated with insomnia, as reviewed in Peltzer and Pengpid[15],[16] include (1) sociodemographic factors, such as increasing age, female sex, lower socioeconomic status, and urban residence, (2) stressors including childhood adversity, mental distress, and lack of social support, and (3) health status variables including functional disability, multimorbidity, various specific chronic conditions such as obesity, arthritis and rheumatic disorders, and health risk behaviors such as physical inactivity and smoking. In addition, stressful life,[17] different types of discrimination experiences,[18],[19],[20],[21],[22] food insecurity,[23],[24],[25] history of pain,[9],[13],[26],[27] underweight,[28] poor vision,[29] and tooth loss[30] were found to increase the odds of insomnia symptoms or other sleep disturbances. A review of prospective studies among older adults found that depressed mood, physical illness, and female sex increased the risk of future sleep disturbances in later life.[7]
This study aimed to estimate the prevalence and correlates of insomnia symptoms among older adults in a national population survey in India in 2017-2018.
| Methods | | |
Sample and procedures
Cross-sectional data from the nationally representative Longitudinal Ageing Study in India Wave 1, 2017–2018 were analyzed (the overall household response rate is 96%, and the overall individual response rate is 87%).[31] Interview, physical measurement, and biomarker data were collected from individuals aged 45 and above and their spouses, regardless of age, in a household survey. Details of the sampling strategy have been described elsewhere.[31] The study was approved by the Indian Council of Medical Research (ICMR) Ethics Committee and written informed consent was obtained from the participants.[31]
Measures
Outcome measure
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 did you feel unrested during the day, no matter how many hours of sleep you had?” Responses options were “never, rarely (1–2 nights per week), occasionally (3–4 nights per week), and frequently (5 or more nights per week).”[31] Sleep problems were coded as “frequently” for the any of the four symptoms as one.[32] In addition, participants were asked about the frequency of taking a nap during the day and the past month use of any medications or other treatments to help with sleep.
Exposure variables
Sociodemographic information included age (years), sex (male, female), education (none, <5 years, 5–9 years, and ≥10 years), residence (rural and urban), and subjective socioeconomic status. The latter was sourced from the item, “Please imagine a ten-step ladder, where at the bottom are the people who are the worst off – who have the least money, least education, and the worst jobs or no jobs, and at the top of the ladder are the people who are the best off – those who have the most money, most education, and best jobs. Please indicate the number given (1–10) on the rung on the ladder where you would place yourself.”[31] Socioeconomic steps 1–3 were classified as poor, 4–5 as medium, and 6–10 as high socioeconomic status.
Food insecurity was assessed with four questions, (1) “In the past 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 past 12 months, were you hungry but did not 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 past 12 months because there was not enough food in your household?”[31] Any positive response to the four questions was scored as one.
Feeling alone was assessed with one item “How often did you feel alone?” (in the past week) from the Center for Epidemiological Studies Depression Scale-10[33] and was coded as often (3 or 4 days) or most or all of the time (5–7 days) = 1 and rarely or never (<1 day), or sometimes (1 or 2 days) = 0.
Discrimination experiences were assessed with the six-item Everyday Discrimination Scale (EDS) (Short version).[34] Response options ranged from 1 = “never” to 6 = “almost every day,” and were dichotomized to “never” = 0 and “ever” (collapsing those reporting “less than once a year” or greater into one category) = 1; Cronbach's alpha for the EDS in this study was 0.86.
Other stressors assessed included (1) ill-treatment (“have you felt that you were ill treated in the past year?” Yes/No), (2) victim of violent crime (“in the last 12 months, have you been the victim of a violent crime, such as assault/mugging/threat to life/others?” (Yes/No), (3) disaster exposure causing health effects (“in the past 5 years, has your health been severely affected by disasters such as floods, landslides, extreme cold and hot weather, cyclone/typhoons, droughts, earthquakes, tsunamis, or any other natural calamities?” (Yes/No), (4) man-made incident causing health effects (“In the past 5 years, has your health been severely affected by man-made incidents such as riots, terrorism, building collapses, fires, traffic accidents, or any other man-made incidents?” (Yes/No), (5) unsafe home and/or neighbourhood (“In general, how safe from crime and violence do you feel when you are alone at home? How safe do you feel when walking down your street/locality alone after dark?” (coded complete safe or safe = 0 and not very safe or not safe at all = 1), and (6) poor childhood health (“Would you say your childhood health was very good, good, fair, poor or very poor on the basis of what you remember, or what you heard or perceived from your parents?”) (coded poor or very poor = 1).[31]
Social support was assessed with three dimensions.
- Religiousness and spirituality was measured with four items from the Daily Spiritual Experience Scale,[35] e.g., “Do you think that you have a feeling of deep inner peace?” Responses ranged from 1 = never to 5 = every day in a week, and the summed scores were trichotomized to 4–7 = low, 8–11 = medium, and 12–20 = high. Cronbach's alpha for the DSES in this study was 0.86
- Life satisfaction was measured with the 5-item Satisfaction With Life Scale (SWLS).[36] Total scores ranged from 5 to 35, with 3–25 indicating very high life satisfaction.[36] Cronbach's alpha for the SWLS in this study was 0.86
- Social network was measured with 11 items, e.g., “Eat-out-of-the house (restaurant/hotel).”[31] Responses were coded 1 = daily to at least once a month and 0 = rarely/once a year or never (Cronbach's alpha 0.67).
Chronic conditions were assessed with 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; (8) any neurological, or psychiatric problems such as depression, Alzheimer's/dementia, unipolar/bipolar disorders, convulsions, Parkinson's, etc; and (9) High cholesterol (Yes/No).”[31] Responses for the nine chronic conditions were summed and trichotomized into 0, 1, or ≥2 chronic conditions.
Functional disability was sourced from activities of daily living (ADL) (6 items) and instrumental ADL (IADL) (7 items).[37],[38] Cronbach alpha for the ADL and IADL scale was 0.89. Responses were “Yes/No” and were trichotomized into 0, 1, or ≥2 ADL/IADL items.
Vision was assessed with two questions, (1) “How good is your eyesight for seeing things at a distance such as recognizing a person across the street (or 20 m 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?”[31] Response options ranged from 1 = very good to 5 = very poor and poor near or far vision as defined as “poor or very poor.”
Edentulism was assessed with the question “Have you lost some or all of your natural teeth?” and defined as “lost all natural teeth.”[31]
Symptom-based pain was defined as troubled by pain and required some form of medication or treatment for relief of pain.[31]
Anthropometry
”Height and weight of adults were measured using the Seca 803 digital scale.”[31] “body mass index = 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).”[39]
Symptom-based pain was defined as troubled by pain and required some form of medication or treatment for relief of pain.[31]
Current tobacco use was sourced from two items, (1) “Do you currently smoke any tobacco products (cigarettes, bidis, cigars, hookah, cheroot, etc.)? and (2) Do you use smokeless tobacco (such as chewing tobacco, gutka, pan masala, etc.)?”[31]
Vigorous physical activity
”For vigorous activity, respondents were asked about their involvement in running or jogging, swimming, going to a health center/gym, cycling, digging with a spade or shovel, heavy lifting, chopping, farm work, fast bicycling, and cycling with loads.”[31] Responses were trichotomized into 1 = hardly ever/never, 2 = less than twice a week, and 3 = more than once a week.[40]
Data analysis
Descriptive statistics were used to describe sociodemographic, stressors, social support, health status, and insomnia symptoms. Unadjusted and adjusted logistic regression was used to estimate the prevalence of insomnia symptoms. No multicollinearity was detected. P < 0.05 was considered significant, and missing values were discarded. All statistical operations were conducted with STATA software version 15.0 (Stata Corporation, College Station, TX, USA), taking the multistage sample design into account.
| Results | | |
Sample characteristics
The study sample included 72,262 persons aged 45 years and older (female spouse, any age) from India. [Table 1] describes the sample characteristics. Among those participants who reported having experienced discrimination, the perceived reasons were age 48.9%, financial status 41.8%, caste 12.9%, gender 9.3%, other 8.9%, other aspects of physical appearance 6.3%, religion 5.3%, physical disability 3.9%, and weight 1.6%. The prevalence of insomnia symptoms was 12.7%, 13.2% among women and 11.9% among men [Table 1].
Level of insomnia symptoms
The overall prevalence of insomnia symptoms was 12.7%, which increased from 9.9% in female spouses aged 18–44 years to 15.3% in persons 65 years and older. The overall prevalence of frequent (≥5 nights/week) trouble will falling asleep was 6.3%, and the highest in 45–54-year-old age group (11.8%). The prevalence of overall frequent waking up in the night, waking up too early, and unrested during the day was 6.0%, 6.0%, and 6.1%, respectively. Each of the latter was the highest in the oldest age group (≥65 years) (7.5%, 7.8%, and 7.3%, respectively). The overall prevalence of frequent napping was 10.6%, with 13.5% in the oldest age group, and 2.4% had been on sleep medication or treatment in the past months (8.3% among those with insomnia symptoms) [Table 2].
Associations with insomnia symptoms
In the adjusted logistic regression analysis, food insecurity (adjusted odds ratio [AOR]: 1.41, 95% confidence interval [CI]: 1.25–1.59), feeling alone (AOR: 1.64, 95% CI: 1.46–1.83), having 3–5 discrimination experiences (AOR: 1.53, 95% CI: 1.32–1.78), having two or more chronic conditions (AOR: 1.65, 95% CI: 1.46–1.86), high functional disability (AOR: 1.80, 95% CI: 1.63–1.99), poor distant vision (AOR: 1.32, 95% CI: 1.17–1.49), poor near vision (AOR: 1.19, 95% CI: 1.07–1.33), edentulism (lost all teeth) (AOR: 1.28, 95% CI: 1.06–1.55), underweight (AOR: 1.11, 95% CI: 1.00–1.23), and pain (AOR: 1.71, 95% CI: 1.54–1.89) were positively associated with insomnia symptoms. High subjective socioeconomic status (AOR: 0.85, 95% CI: 0.76–0.96), urban residence (AOR: 0.90, 95% CI: 0.81–0.99), and medium social network (AOR: 0.87, 95% CI: 0.79–0.96) were negatively associated with insomnia symptoms. In addition, in unadjusted analysis, older age (≥60 years), ill-treatment in the past 12 months, victim of violent crime, disaster exposure, man-made incidents, unsafe home and/or neighborhood, and poor childhood health were positively, and male sex, higher education, high spirituality and religiosity, very high life satisfaction, and once a week or more vigorous physical activity were negatively associated with insomnia symptoms [Table 3].
In an adjusted analysis between specific chronic conditions and insomnia symptoms, hypertension, cancer, chronic lung disease, chronic heart diseases, stroke, arthritis, neurological or psychiatric problems, and high cholesterol were significantly positively associated with insomnia symptoms [Table 4]. | Table 4: Associations between specific chronic conditions and insomnia symptoms
Click here to view |
| Discussion | | |
The study found that, in a large national older adult (≥45 years) sample in India in 2017-2018, the prevalence of insomnia symptoms was 12.7%, which is similar to a previous survey in 2007 India (15.0%, ≥50 years),[8] and in Mugalur village near Bangalore (13.0%, ≥60 years),[11] lower than among attendants or relatives of hospital outpatients in South India (18.6% insomnia),[12] and urban dwellers in West Bengal (15.4% insomnia).[14] The proportion of health seeking for insomnia symptoms was 2.4% (8.3% among those with insomnia symptoms) in this study, compared to 0.3% in a study in South India,[12] 15.0% among insomnia patients in an urban population in West Bengal, India,[14] and 8% were using sleeping pills among the elderly in New Delhi.[10]
In unadjusted analysis, older age and female sex increased the odds of insomnia symptoms, but this was no longer the case in the adjusted analysis. Similar results were found in some previous studies,[15],[26],[27],[41] which can be explained by adjusting for chronic conditions, which increase with age. In agreement with previous research studies, this study showed a positive association between lower socioeconomic status,[9],[15],[26] residing in rural areas[42] and insomnia symptoms. It is possible that persons with lower socioeconomic status and those who live in rural areas experience more stressors contributing to more insomnia symptoms.
Consistent with previous results,[18],[19],[20],[21],[22],[23],[24],[25],[28] this survey showed a significant positive association between different stressors such as discrimination experiences (mainly because of age 48.9%, financial status 41.8%, caste 12.9%, and gender 9.3%), food insecurity, underweight status, and insomnia symptoms. In addition, in unadjusted analysis, stressors of ill treatment in the past 12 months, victim of violent crime, disaster exposure, man-made incidents, unsafe homes and/or neighborhood, and poor childhood health were positively associated with insomnia symptoms, which is in line with previous research (childhood adversity,[15],[43] exposure to disaster,[15] traumatic life events,[16] and unsafe neighborhood).[44] Exposure to different types of stressors may generate psychological difficulties that negatively impact on sleep quality.[26]
In line with previous research, functional disability,[15],[16] multimorbodity,[7],[8],[9],[45] history of pain,[9],[13],[16],[26] poor vision,[29] and tooth loss[30] were associated with insomnia prevalence. In case of poor vision, light input may be reduced due to low vision affecting the sleep-wake cycle leading to insomnia symptoms.[29],[46] Furthermore, consistent with previous research, specific chronic conditions, such as hypertension,[47],[48] heart disease,[8],[15],[47] stroke,[8] chronic lung diseases,[8],[15],[16],[26] arthritis and rheumatic disorders,[15],[26],[49] and high cholesterol[15],[50] were found to be associated with insomnia symptoms. Mental distress, feeling alone, and psychiatric problems such as depression were found associated with insomnia symptoms in this study, which is consistent with previous research.[7],[8],[9],[27],[45]
While some studies[14],[26],[47] found a positive association between tobacco use and insomnia symptoms, this study did not find such an association, perhaps because of the very high prevalence of current tobacco use (30.4%) in this study. In agreement with previous research,[7],[51] this study showed in univariate analysis that participation in vigorous physical activity was protective against insomnia symptoms. Having a medium social network, and in univariate analysis, high spirituality, and religiosity and very high life satisfaction were in this study protective against insomnia symptoms, which is conform with previous results (high religiosity[15] and social cohesion[27]).
Study strength and limitations
The strength of the study was a nationally representative sample of older adults in India and the use of standardized measures adapted from the Health and Retirement Study. The self-report of most data may have their limitations. Furthermore, this study was based on cross-sectional data, and we therefore cannot ascribe causality to any of the associated factors in the study. Family history of sleep disorders and dietary behavior were not assessed in this survey but should be in included in future research. Insomnia symptoms were not assessed with the latest diagnostic criteria, and other sleep disturbances, such as obstructive sleep apnea, were not assessed, and sleep duration was only assessed on a subsample.
| Conclusions | | |
More than one in ten older adults in India had insomnia symptoms. Sociodemographic factors (lower socioeconomic status and rural residence), stressors (food insecurity, feeling alone, and discrimination experiences), lack of social support, and poor health status (chronic conditions, functional disability, poor vision, edentulism, underweight, and pain) were identified for insomnia symptoms, which can be utilized in targeting interventions.
Acknowledgments
”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.”
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
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[Table 1], [Table 2], [Table 3], [Table 4]
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