Prevalence and patterns of comorbidities in people with disabilities and their associated socio-demographic factors

The presence of comorbidities among individuals with disabilities worsens their already complex health and social circumstances. This study aims to explore prevalence and patterns of morbidities among persons with disabilities in Bangladesh and identify associated socio-demographic factors. Data from 4270 persons with disability was analysed extracted from the 2021 Bangladesh National Household Survey on Persons with Disability. Outcome variable considered was the occurrence of morbidity among persons with disabilities. Explanatory variables encompassed factors at the individual, household, and community levels. Adjusted and unadjusted multilevel mixed-effects logistic regression model was used to explore association of outcome variable with explanatory variables. We found that approximately half of individuals with disabilities experienced one or more morbidities, with chronic conditions being the most prevalent (44%). Around 42% of total persons with disability were unable to work. Specifically, hypertension (18.3%), diabetes (9.1%), and heart problems (17.1%) were prevalent chronic conditions. The likelihood of experiencing comorbidity was found to be higher among females (aOR 1.3, 95% CI 1.1, 1.7), increase year of education (aOR, 1.1, 95% CI 1.0–1.2), and those from wealthier households (aOR 1.6, 95% CI 1.2, 2.2). This underscores the need for targeted policies and interventions addressing their distinct healthcare needs.


Analysed sample
This study specifically targeted individuals aged 2 and older (excluding those under 2, as identifying the need for assistive instruments or detecting disabilities is notably challenging in that age group in Bangladesh).We focused on individuals with various types of disabilities as intended.Out of all participants in the survey, a total of 4270 individuals reported having a disability, and they were included in our analysis.

Outcome variable
Our primary objective was to investigate the occurrence of morbidities (presence of illness or health conditions) among individuals with disabilities (functional limitations or restrictions in performing activities due to impairments).Relevant data were gathered by posing two independent sets of questions.Initially, questions aimed at determining disability status were administered, followed by inquiries concerning morbidity status.To accomplish this, data collectors meticulously assessed the status of all household members, inquiring whether any reported members utilized assistive instruments, such as hearing aids, to lead a normal life.The identified respondents or their actual caregivers (for children under 18 years of age) were then subjected to a series of questions to ascertain whether the reported difficulty qualified as a disability.The Washington Group Questions for child and adult were employed for this purpose.The selected group of respondents or their actual caregivers were also presented with two additional questions to determine the presence of existing morbidities.Firstly, they were asked, "Do you (or the name of children under 18 selected for disability-related questions) have any other health or physical problems besides your disability?"Those responding affirmatively to this initial question were subsequently queried, "Which type of health-related or physical health problems do you have?"A comprehensive list of morbidities, including conditions such as blood pressure, diabetes, asthma, epilepsy, heart problems, physical/movement problems, and other health and physical issues, was provided for respondents to choose from.An option was also given to indicate if the health condition was not listed.Using these responses, we formulated a straightforward classification to discern whether a person with a disability had a morbidity or not and considered as the outcome variable.

Explanatory variables
Several explanatory variables were included.They were selected in three stages.In the first stage, we generated a list of relevant variables through compressively reviewing relevant literature covering LMICs and Bangladesh 9,10,[20][21][22] .The availability of these selected variables was then checked in the survey during the second stage.Finally, the available variables were considered in this study and classified as individual, household, and community-level factors.Individual-level factors include the age of the respondents (children aged 2-17, adults aged 18-34, late adult aged 35-59, older individuals aged 60 or more), gender (male vs. female), respondents' employment status (agriculture, physical workers, business, service, students, housewives, unable to work, and others), educational attainment (no education, primary, secondary or higher), religion (muslim vs. others), and marital status (married, unmarried, and widow/divorced/separated). Household wealth status (poorest, poorer, middle, richer, richest) was considered as household-level factors.The household wealth status was created by the survey authority using principal component analysis, considering several variables related to household wealth, such as ownership of a radio or television and household roof types.Place of residence (rural vs. urban) and administrative division (Barishal, Chattogram, Dhaka, Khulna, Mymensingh, Rajshahi, Rangpur, Sylhet) were included as community-level factors.

Statistical analysis
Descriptive statistics were used to explore the background characteristics of the respondents.Pearson chi-square test was used to identify the significant differences of the occurrence morbidity among person with disability with explanatory variables at the individual, household and community level.Two level (household, cluster) multilevel logistic regression models were used to explore the associations of morbidities among persons with disability with individual, household, and community level factors.The nested structure of the NSPD data, where individuals are nested within household and households are nested within clusters, necessitated the use of multilevel modelling 23 .Previous studies have found that multilevel modelling provides comparatively better results for such structured data than simple logistic regression models 24 .Two separate models were run for children aged 2-17 and adults aged 18-95 years.Each model was adjusted for the considered explanatory variables.Multicollinearity was checked before running each model.Sampling weight were considered in all analyses.Results were recorded as adjusted odds ratios (aOR) along with their 95% confidence intervals (95% CI).All statistical analyses were performed using Stata software version 14.0 (StataCorp.org,College Station, Texas, USA).All methods are performed according to the guidelines.

Ethical approval
The survey we analysed conducted by the Bangladesh Bureau of Statistics.Before conducting the survey, they collected the ethical approval from the Bangladesh Medical Research Counsel of the Government of Bangladesh and from their own internal review broad.Informed consent was obtained from all the respondents before conducting interviews.When respondents were unable to provide informed consent, we obtained it from their legally authorized representatives, including husbands of women included in the survey.The shared us the nonidentifiable individual's data for this study based on our interest to conduct this particular research.Since we only get data in non-identifiable form, we do not need any further ethical approval.

Background characteristics of the study population
Table 1 presents the background characteristics of the respondents.Approximately 20% of the total respondents were children aged between 2 and 17 years.Around 59% of the total respondents were male.The majority of respondents had not received any formal education (56.9%).In terms of occupation, a significant proportion of persons with disability were unable to work (41.8%), followed by housewives and students.Nearly 48% of the total respondents were married at the time of the survey.Approximately 27% of the total respondents were resided in poorest households.The majority of individuals resided in rural areas (80.7%).The largest portion of persons with disability resided in the Dhaka division (21.6%) followed by Chattogram (16.2%) and Rangpur (14.7) divisions (Fig. 1).

Prevalence of morbidities among persons with disability in Bangladesh
Table 2 presents the percentage and types of disability and morbidities among persons with disability.Physical impairment (42.5%) was comments from of disability following by visual impairment (14.1%) and multidimensional disability (11.7%).Approximately half of the total persons with disabilities were identified as having at least one morbidity (50.0%, 95% CI: 48.4-51.8).The most prevalent types of morbidity were physical or movement problems (34.1%)following by hypertension (18.3%).Other commonest forms of morbidities were heart problems (17.1%),diabetes (9.1%), asthma (9.0%), and epilepsy (3.9%).

Distribution of morbidities among persons with disability in Bangladesh across respondent's characteristics
The percentage distribution of morbidities among persons with disability across respondent's individual, household, and community level characteristics are presented in Table 3.The prevalence of morbidities was found to be higher among older disabled persons aged 60 or more, females, persons with no formal education, those who were widowed, divorced, or separated, and those who resided in the richest households.The prevalence of morbidities varied significantly across several explanatory variables considered, except religion and place of residence.www.nature.com/scientificreports/

Factors associated with morbidities among persons with disability in Bangladesh
The likelihoods of morbidities among persons with disability with individual, household, and community-level characteristics are presented in Table 4.We found that the likelihood of morbidities increased (aOR, 1.1, 95% CI 1.0-1.2) with the level of education among persons with disabilities.Female persons with disability reported a higher likelihood of morbidity (aOR 1.3, 95% CI 1.1-1.7)compared to male persons with disability.The likelihoods of experiencing morbidities were found lower among unmarried, divorced, and separated individuals compared to married persons with disability.Persons with disability residing in the wealthiest households reported a 1.6 times higher likelihood of morbidity (aOR 1.6, 95% CI 1.2-2.3)compared to those residing in the poorest households.We also reported lower likelihoods of morbidities among persons with disability residing in the Dhaka (aOR 0.7, 95% CI 0.5-1.0),Mymensingh (aOR 0.5, 95% CI: 0.3-0.7),and Rangpur (aOR 0.7, 95% CI 0.5-1.0)division as compared to those persons with disability residing in the Barisal division.

Discussion
This study aimed to explore the prevalence of morbidities among persons with disability in Bangladesh and their connections to individual, household, and community-level factors.Our findings reveal that nearly half of all persons with disability in Bangladesh experience at least one morbidity, encompassing chronic conditions and epilepsy.The likelihood of encountering these additional morbidities among individuals with disabilities was notably higher for those with relatively higher levels of education, females, married respondents, those residing in the wealthiest and those living in the Dhaka, Mymensingh, and Rangpur divisions.These results are robust, given the comprehensive analysis of a large national-level sample and the consideration of a wide array of factors at the individual, household, and community levels.As such, these findings are poised to inform evidence-based policies and programs aimed at enhancing the well-being of the persons with disability in Bangladesh as well as other LMICs 25 .
The estimated prevalence of about 50% of health issues among individuals with disabilities is a cause for concern.Unfortunately, we were unable to compare this finding with the available estimates in LMICs and Bangladesh due to the lack of relevant data 6,26,27 .This higher prevalence indicates that the challenges faced by the persons with disabilities are multidimensional, encompassing issues related to both disability and morbidity, either individually or in combination 28,29 .This underscores the need for a greater role of healthcare services to support this group.However, this is particularly concerning for Bangladesh, similar to other LMICs, where healthcare facilities are mostly not disable-friendly in terms of access, compounded by the common characteristic of overcrowding 8 .The higher prevalence of disability among comparatively lower-educated and poor individuals exacerbates the situation 30 .Considering their requirement for long-term financial support, the inadequacy of such support in Bangladesh and other LMICs becomes even more pronounced.As of the recent national budget in 2023, disabled individuals receive only BDT 800 (~ 8 USD) per month 31,32 .This meagre amount of financial support is supplemented by the fact that only 4% of the total persons with disability receives financial assistance from the government, with 47.4% having received any allowances at least once in their lifetime 16 .Challenges of this nature present an insurmountable burden to achieving the Sustainable Development Goals if these individuals are excluded from the mainstream development process in Bangladesh 4 .
More than 44% of persons with disabilities have reported experiencing various chronic conditions, including diabetes (9%), hypertension (18%), and heart problems (17%).These prevalence estimates are consistent with the average rates of these conditions in Bangladesh 6,11 .However, they also highlight a growing concern due to the fact that chronic conditions often demand meticulous management and long-term care, aspects that can pose substantial challenges for people with disabilities in Bangladesh 18 .For instance, maintaining a healthy lifestyle through ensuring access to nutritious food and engaging in regular physical exercise is fraught with difficulties for this demographic 17,31 .Additionally, the financial support they receive, combined with their personal capacities, may not suffice to enable consistent access to healthcare services required for effectively managing chronic conditions 6,33 .Consequently, these dual challenges may result in untreated and unmanaged chronic conditions, potentially leading to the emergence of further health complications and premature fatalities 14 .
We observed a slight increase in the likelihood of morbidities with the rising level of education among adults with disabilities.The reasons behind these associations are mostly unknown.However, it is plausible that individuals with higher levels of education in Bangladesh may face a greater burden of chronic conditions, which often remain untreated and subsequently contribute to disability in later stages of life 34 .This is particularly noteworthy given the elevated occurrence of disability resulting from road traffic injuries among relatively higher educated individuals in Bangladesh 35 .Furthermore, higher likelihood of morbidities among persons with disability in the wealthiest households and females further bolsters this understanding.However, we could not find any logical reasoning about the divisional level variations in the likelihoods of morbidity among the persons with disability, as reported in this study.Unfortunately, we were unable to validate these findings and explore possible pathways due to the lack of available literature.As such, we recommend further studies to delve into this aspect.
This study has several strengths and a few limitations.The data analyzed in this study were extracted from a nationally representative survey with a large sample size.The estimates reported in this study are the very first of their kind in Bangladesh as well as other LMICs.The findings of this study have been adjusted for a comprehensive range of confounding factors, carefully selected through an extensive literature search and rigorous statistical analysis.Advanced statistical techniques were employed to determine the associations.Consequently, these findings will aid policy makers in formulating evidence-based policies and programs that ultimately contribute to the betterment of persons with disability.However, the primary limitations of this study lie in the analysis of cross-sectional data.Thus, the findings presented in this study are correlational only rather than causal.The survey relies on self-reported morbidity data, which could potentially result in the misreporting of certain forms of morbidities.Furthermore, the survey employs the Washington Group's Module to assess disability, utilizing a set of questions answered by respondents or their caregivers to identify individual disabilities.The reliance on self-reported data introduces the potential for reporting bias.However, any such bias is assumed to be random, and the use of this globally recognized disability measuring tool provides evidence of the accuracy of the reported estimates.We excluded children under 2 years of age due to the potential for misreporting or undiagnosed disability status.Furthermore, we aggregated all types of disabilities into an overarching variable representing disability status.This reclassification might potentially underestimate the nuanced effects of specific disabilities.For example, mental illness and physical impairment differ significantly, and the associated morbidities in these two groups can yield distinct consequences and explanations.However, investigating these distinct effects falls outside the scope of this study.Our dichotomized reclassification of disability status aligns with global literature practices and is supported by the Washington Group's Module for assessing disability.Furthermore, various

Conclusion
Approximately 50% of persons with disabilities reported experiencing of at least one morbidity.The most prevalent types of morbidity among persons with disability were various chronic conditions, such as hypertension, diabetes, and heart problems.The likelihood of experiencing morbidity was found to be higher among those with relatively higher education levels, females, and the most affluent persons with disability.These findings underscore the necessity for enhanced support in both financial and healthcare access domains.Increasing financial allowances for persons with disability, alongside the implementation of policies and programs that ensure disability-friendly healthcare services, becomes imperative in light of these insights.

Figure 1 .
Figure 1.Regional distribution of persons with disability in Bangladesh.

Table 1 .
Background characteristics of the respondents, Bangladesh, 2021, (N = 4,270).All estimates are weighted.+ Physical worker includes industry or factory labour, transportation worker, day labour, rickshaw/ van driver, and fisherman.++ Other occupation includes looking for work, beggar.

Table 2 .
Patterns of disability and incidence of morbidities among persons with disability in Bangladesh.