Health-related quality of life among patients with type 2 diabetes mellitus using EuroQol five-dimension five level: A cross-sectional study from an urban health training center, Coimbatore, India

Abstract

BACKGROUND:

Diabetes mellitus significantly impacts health-related quality of life (HRQoL). Data from urban primary care settings in South India remain limited. This study assessed HRQoL among type 2 diabetes mellitus (T2DM) patients and identified demographic and clinical determinants associated with EuroQol five-dimension five level (EQ-5D-5L) index and EQ visual analogue scale (EQ-VAS) scores.

MATERIALS AND METHODS:

A hospital-based cross-sectional study was conducted (April–July 2025) at the urban health training center (UHTC), Coimbatore, Tamil Nadu, India. A total of 279 T2DM patients (aged ≥18 years) were enrolled using consecutive sampling. HRQoL was assessed using the licensed Tamil and English EQ-5D-5L questionnaire. Data were analyzed using R software; Chi-square tests and independent t-tests were applied (P < 0.05).

RESULTS:

Mean EQ-5D-5L index was 0.63 ± 0.37 and EQ-VAS was 72.6 ± 18.0. Pain/discomfort (52.1%) and anxiety/depression (43.2%) were the most affected dimensions. Microvascular complications (neuropathy P = 0.001; nephropathy P = 0.001; retinopathy P = 0.003), longer disease duration (P = 0.001), hospitalization (P = 0.001), and lower income (P = 0.003) were significantly associated with poorer HRQoL.

CONCLUSION:

Pain/discomfort and psychological distress are the most impaired HRQoL domains in urban South Indian T2DM patients. Microvascular complications, longer disease duration, hospitalization, and lower socioeconomic status are key determinants. These findings support integrating HRQoL monitoring within primary care non-communicable diseases (NCD) programmers under the National Programmed for Prevention and Control of Cancer, Diabetes, Cardiovascular Diseases and Stroke (NPCDCS) framework.

Introduction

Diabetes mellitus is a global public health challenge, with the prevalence of type 2 diabetes mellitus (T2DM) rising disproportionately in low- and middle-income countries, including India. India currently has one of the largest diabetes burdens worldwide, affecting over 101 million people.[1] Unlike acute illnesses, T2DM is a progressive chronic condition involving lifelong management that substantially affects the overall health-related quality of life (HRQoL) of affected individuals.

HRQoL is a multidimensional construct encompassing physical, functional, psychological, and social domains of well-being as perceived by the patient.[2] Its measurement plays a central role in comprehensive disease management and in evaluating therapeutic outcomes beyond biomedical parameters alone. Several studies have identified poor Glycemic control, advancing age,[3,4] microvascular complications, longer disease duration, and insulin dependency as key determinants of reduced HRQoL in T2DM populations.[5,6,7]

Furthermore, lifestyle-based interventions targeting these domains have demonstrated meaningful improvements in HRQoL across diverse populations[8]

Various validated tools have been used globally to measure quality of life in T2DM,[9,10] including the SF-36and the EQ-5D, originally developed in 1991Among these, the EuroQol five-dimension five level (EQ-5D-5L), developed by the EuroQol Research Foundation, is widely regarded for its brevity, cross-cultural validity, and utility in economic analyses. A systematic review confirmed the validity and reliability of the EQ-5D-5L specifically in T2DM populations.[11] Despite widespread international use, Indian literature employing the EQ-5D-5L in urban primary care settings remains sparse, particularly from South India, with most data derived from tertiary care contexts.[12,13,14]

Study novelty

This study is among the first to evaluate HRQoL in T2DM patients at the urban primary care level in South India using the licensed Tamil and English versions of the EQ-5D-5L. Unlike prior Indian studies predominantly from tertiary care settings, this investigation provides primary care-specific evidence directly relevant to community-level diabetes management and health policy in India.

Primary objective

To assess HRQoL among T2DM patients attending an urban health training center (UHTC) using the EQ-5D-5L tool and to identify demographic and clinical determinants associated with EQ-5D-5L index and EuroQol visual analogue scale (EQ-VAS) scores.

Secondary Objectives

(i) To compare EQ-5D-5L dimension scores across demographic sub-groups; (ii) to examine the association between microvascular complications and HRQoL dimensions; and (iii) to explore interrelationships between EQ-5D-5L domains and glycemic markers.

Hypothesis

T2DM patients with microvascular complications, longer diabetes duration, poor glycemic control, and lower socioeconomic status will demonstrate significantly lower EQ-5D-5L index and EQ-VAS scores.

Conceptual framework

The conceptual framework [Figure 1] is grounded in the WHO HRQoL model (Wilson and Cleary, 1995), which encompasses biological/physiological factors, symptom status, functional status, and general health perceptions. Clinical determinants (glycemic control, complications, disease duration, medication type) and sociodemographic factors (age, gender, income, education) act as upstream determinants influencing HRQoL outcomes as measured by the EQ-5D-5L.

Figure 1.

Conceptual framework illustrating the relationship between sociodemographic determinants (age, gender, education, income, occupation) and clinical determinants (diabetes duration, glycemic control, microvascular complications, medication type, hospitalization) with HRQoL outcomes as measured by the EQ-5D-5L instrument, grounded in the WHO HRQoL conceptual model (Wilson and Cleary, 1995; adapted for urban primary care setting, Coimbatore, India). EQ-5D-5L = EuroQol five-dimension five level; HRQoL = Health-related quality of life

Materials and Methods

Study design and setting

This was a hospital-based, descriptive cross-sectional study conducted from April 2025 to July 2025 at the (UHTC) attached to a medical institution in Coimbatore, Tamil Nadu, India. The UHTC serves as a primary care facility for the urban population and provides outpatient services for non-communicable diseases (NCD), including T2DM.

Study participants and sampling

Sample size was calculated based on the study by Tan MHP[5] conducted among a comparable diabetic population using EQ-5D dimensions. Using an online sample size calculator (Raosoft Inc., 2004),[15] with an expected proportion of 50%, margin of error of 5%, and 95% confidence level, the minimum required sample size was estimated as 279. Consecutive sampling was employed; all T2DM patients attending OPD during the study period who met the eligibility criteria were enrolled until the required sample size was achieved. This sampling strategy ensured minimal selection bias in a real-world primary care context.[16]

Inclusion criteria

All patients aged ≥18 years with confirmed T2DM based on American Diabetes Association ADA diagnostic criteria, attending the OPD during the study period, willing to provide written informed consent.

Exclusion criteria

Patients unable to respond independently due to severe physical or psychiatric illness, neurological disorders impairing communication, diabetic pregnant women, and patients who refused consent were excluded.

Data collection tool and technique

The EQ-5D-5L validated questionnaire developed by the EuroQol Research Foundation was used as the primary instrument.[16] Both English and Tamil licensed versions were administered to ensure linguistic and cultural validity; the use of the official EuroQol-licensed Tamil version confirms cultural adaptation. The EQ-5D-5L comprises five dimensions—mobility, self-care, usual activities, pain/discomfort, and anxiety/depression—each scored on five severity levels. The EQ-5D-5L index score was calculated using the Indian value set,[7] and EQ-VAS scoring followed the methodology of Chuang et al.[17]

Demographic and clinical data were retrieved from patient medical records. The demographic checklist and EQ-5D-5 L questionnaire were handed into the patients and collected after completion in the clinic between 8 am and 1 pm. The detailed data for DM history, laboratory values, presence and type of complications were obtained from the medical records. The information from the illiterate patients was collected by the researcher after reading the questions for them. Diagnosis of diabetic complications including nephropathy and neuropathy as well as retinopathy was performed and recorded in the patients’ profile.

Ethical consideration

The study was approved by the Institutional Ethics Committee (IEC Approval Number: PSG/IHEC/2025/APPR/EXP/063) prior to commencement. Written informed consent was obtained from all participants. Confidentiality of data was strictly maintained throughout the study. The study protocol adhered to the ethical principles of the Declaration of Helsinki.

Statistical analysis method

Data analysis was performed using R software (version 4.x). Continuous variables were expressed as mean ± standard deviation (SD) with 95% confidence intervals; categorical variables as frequencies and percentages. Chi-square tests were used for categorical comparisons of EQ-5D-5L dimension problem proportions, and independent t-tests or one-way ANOVA for mean score comparisons across groups. Pearson’s correlation analysis was performed for EQ-5D-5L domain interrelationships. Statistical significance was defined as P < 0.05.

Results

Clinical and demographic characteristics

A total of 279 T2DM patients with a mean aged 62.1 ± 12.7 years were analyzed [Table 1]. The majority were above 60 years (51%), and females predominated (n = 148; 53%). Most had school-level education (61%), were married (87%), and belonged to income Class I (≥₹10,000/month; 60%). Regarding diabetes management, 82% were on oral hypoglycemic agents and 66% had a diabetes duration of less than 10 years. Neuropathy was the most prevalent microvascular complication (37%), followed by retinopathy (32%) and nephropathy (8%). Ischemic heart disease was noted in 5%, and 35% had a history of diabetes-related hospitalization.

Table 1.

Distribution of patients’ demographic and clinical characteristics (n=279)

Characteristics		Category		n (n=279)		Percentage (%)
Age group (years)		≤50		52		19
		51–60		84		30
		>60		143		51
Gender		Male		131		47
		Female		148		53
Education		Graduate		48		17
		School education		171		61
		Illiterate		60		22
Occupation		Employed		140		50
		Unemployed		139		50
Marital status		Married		242		87
		Others		37		13
Monthly income		Class I (≥₹10,000/month)		168		60
		Others (<₹10,000/month)		111		40
Diabetes medication		Oral hypoglycaemic agents		229		82
		Insulin therapy		50		18
T2DM blood glucose (mg/dL)		FBS (Mean±SD)		128.69±45.55		—
		PPBS (Mean±SD)		206.62±56.13		—
Duration of T2DM		<10 years		183		66
		≥10 years		96		34
Neuropathy		Yes		102		37
		No		177		63
Retinopathy		Yes		89		32
		No		190		68
Nephropathy		Yes		21		8
		No		258		92
Ischemic heart disease (IHD)		Yes		14		5
		No		265		95
Diabetes-related hospitalization		Yes		97		35
		No		182		65

FBS=Fasting Blood Sugar; PPBS=Post-prandial Blood Sugar; IHD=ischemic heart disease; SD=Standard Deviation

Table 2 presents mean EQ-5D-5L index and EQ-VAS scores by demographic characteristics, stratified by gender. Monthly income was significantly associated with EQ-5D-5L index scores in males (P = 0.050) and overall (P = 0.024), and with EQ-VAS in males (P = 0.048) and overall (P = 0.003). Duration of diabetes was significantly associated with EQ-5D-5L index in males (P = 0.001) and overall (P = 0.003). Diabetes-related hospitalization was significantly associated with EQ-5D-5L index across all groups (P = 0.001 each).

Table 2.

Mean EQ-5D-5L index and EQ-VAS scores by demographic characteristics, stratified by gender (selected variables)

Variable		Category		EQ-5D index male		EQ-5D index female		EQ-5D index total		EQ-VAS male		EQ-VAS female
Age group		≤50		0.647±0.428		0.625±0.431		0.635±0.426		77.2±18.1		74.8±19.0
		51–60		0.705±0.344		0.640±0.416		0.664±0.390		76.9±21.2		71.5±17.4
		>60		0.652±0.348		0.608±0.314		0.632±0.332		72.6±16.1		68.0±18.9
		P		0.765		0.899		0.807		0.373		0.223
Monthly income		Class I		0.704±0.343		0.654±0.386		0.682±0.362		76.3±17.6		73.3±18.1
		Others		0.557±0.387		0.592±0.363		0.581±0.369		69.4±17.4		67.9±18.5
		P*		0.050*		0.315		0.024*		0.048*		0.077
Duration T2DM		<10 years		0.748±0.304		0.643±0.366		0.690±0.343		74.1±17.4		70.6±18.3
		≥10 years		0.522±0.402		0.579±0.393		0.550±0.397		75.0±18.6		70.4±19.0
Hospitalization		Yes		0.519±0.390		0.467±0.348		0.494±0.370		73.7±17.5		69.7±17.2
		No		0.758±0.307		0.693±0.366		0.721±0.342		74.9±18.0		71.0±19.0
		P*		0.001*		0.001*		0.001*		0.717		0.680

*P<0.05. Values expressed as Mean±SD. EQ-5D=EuroQol Five Dimension; VAS=Visual Analogue Scale; T2DM=Type 2 diabetes mellitus

EQ-5D-5L dimension analysis

Analysis of the EQ-5D-5L responses demonstrated varying degrees of problem severity across the five health dimensions [Figure 2]. The pain/discomfort dimension showed the highest problem burden: 52.1% of participants reported some degree of pain or discomfort. Anxiety/depression was the second most affected dimension, with 43.2% reporting problems. Mobility (42.7%), self-care (44.4%), and usual activities (47.6%) also showed substantial problem rates.

Figure 2.

Bar chart illustrating EQ-5D-5L response distribution across five health dimensions (mobility, self-care, usual activities, pain/discomfort, and anxiety/depression) showing the proportion of patients at each severity level among T2DM patients (N = 279). EQ-5D-5L = EuroQol five-dimension five level; T2DM = Type 2 diabetes mellitus

Table 3 presents the association between demographic and clinical characteristics and EQ-5D-5L problem proportions. Gender was significantly associated with self-care (P = 0.030) and anxiety/depression (P = 0.021), with females reporting higher burden in both domains. Monthly income was significantly associated with pain/discomfort (P = 0.001) and anxiety/depression (P = 0.003). Longer diabetes duration (≥10 years) was significantly associated with all major dimensions. All microvascular complications showed statistically significant associations with most EQ-5D-5L dimensions (P < 0.05), with nephropathy demonstrating the strongest associations (86% problem rate for both mobility and pain/discomfort; P = 0.001 each). Diabetes-related hospitalization was significantly associated with all five dimensions (P < 0.05).

Table 3.

Proportion of patients (%) reporting any problem in EQ-5D-5L dimensions by demographic and clinical characteristics

Variable		Category		Mobility %		P		Self-care %		P		Usual Act. %		P		Pain %		P		Anx/Dep %
Gender		Male		42		0.999		35		0.030*		47		0.310		50		0.693		34
		Female		42				49				53				53				49
Monthly Income		Class I		40		0.629		38		0.061		46		0.096		43		0.001*		35
		Others		44				50				57				64				53
Duration T2DM		<10 yrs		34		0.001*		38		0.078		45		0.018*		45		0.009*		37
		≥10 yrs		57				50				60				62				51
Neuropathy		Yes		58		0.001*		59		0.001*		63		0.002*		64		0.002*		52
		No		33				33				43				44				36
Retinopathy		Yes		55		0.003*		51		0.074		60		0.044*		69		0.001*		47
		No		36				38				46				43				39
Nephropathy		Yes		86		0.001*		76		0.002*		81		0.006*		86		0.002*		67
		No		38				40				48				48				40
Hospitalization		Yes		63		0.001*		61		0.001*		69		0.001*		72		0.001*		53
		No		31				32				40				40				36

*P<0.05. IHD=ischemic heart disease; EQ-5D-5L=EuroQol five-dimension five level. Percentages represent the proportion reporting any degree of problem in the respective dimension

Correlation heatmap analysis

A correlation heatmap was generated to examine the interrelationships between EQ-5D-5L domains, EQ Likert Summary Score (EQ-LSS), EQ-VAS, and age [Figure 3]. The EQ-LSS index demonstrated strong negative correlations with pain/discomfort (r = −0.76), usual activities (r = −0.66), and anxiety/depression (r = −0.63). EQ-VAS showed moderate negative associations with pain/discomfort (r = −0.26) and anxiety/depression (r = −0.23). Among dimensions, pain/discomfort was strongly correlated with anxiety/depression (r = 0.40), suggesting co-occurrence of physical and psychological distress. Self-care was positively correlated with usual activities (r = 0.38) and mobility (r = 0.51). Fasting blood sugar (FBS) showed a modest inverse association with EQ-VAS (r = −0.10) and post-prandial blood sugar (PPBS) with EQ-LSS (r = 0.27), indicating that suboptimal glycemic control is associated with lower HRQoL. Age did not show a consistent correlation with EQ-5D-5L indices. These findings are associative in nature; causal inference cannot be drawn from this cross-sectional design.

Figure 3.

Correlation heatmap displaying Pearson’s correlation coefficients between EQ-5D-5L domains, EQ-LSS index, EQ-VAS, fasting blood sugar (FBS), post-prandial blood sugar (PPBS), and age among T2DM patients (N = 279). Color intensity reflects the magnitude of correlation; red indicates positive and blue indicates negative correlations. EQ-.

Discussion

This cross-sectional study evaluated HRQoL among 279 T2DM patients attending an UHTC in Coimbatore, South India. The overall mean EQ-5D-5L index score of 0.63 ± 0.37 and EQ-VAS score of 72.6 ± 18.0 are consistent with findings from other South Indian studies. A 2022 study of T2DM patients in South India by Natarajan and Mokoboto-Zwane reported comparable HRQoL impairment, identifying female gender, longer diabetes duration, and the presence of complications as dominant predictors of reduced quality of life.[12] A recent study among urban T2DM patients in Tamil Nadu similarly reported that pain/discomfort and anxiety/depression were the most affected EQ-5D domains.[18] In contrast, a study from Ahmedabad, Gujarat, reported a higher EQ-5D index of 0.80 and EQ-VAS of 78.83,[5] likely reflecting differences in patient demographics, facility type, and regional healthcare infrastructure.

Internationally, primary care settings in Indonesia reported an average EQ-5D score of 0.86.[19] A comprehensive systematic review and meta-analysis by Afshari et al.[11] on EQ-5D-5L properties in T2DM confirmed that the instrument reliably discriminates HRQoL across clinical subgroups, with ceiling effects more pronounced in studies without complications. A study from a Malaysian university hospital[5] demonstrated that nephropathy (P = 0.029), retinopathy (P < 0.001), neuropathy (P = 0.004), and foot ulcer (P = 0.039) were each independently associated with poor HRQoL across multiple dimensions, closely mirroring the pattern observed in the present study.

Gender differences in HRQoL were limited overall. Significant differences were found only in self-care (P = 0.030) and anxiety/depression (P = 0.021), with females reporting higher burden in both domains. A scoping review of quality of life and diabetes in India[14] highlighted that female T2DM patients consistently report worse HRQoL in psychosocial domains, attributed to differential access to healthcare, social support, and coping mechanisms. This is consistent with findings from North Indian[20] and Eastern Indian populations^.[20,21]

Longer diabetes duration (≥10 years) was significantly associated with poorer HRQoL across mobility (P = 0.001), usual activities (P = 0.018), pain/discomfort (P = 0.009), and anxiety/depression (P = 0.035), reflecting the progressive nature of T2DM and cumulative complication burden. Nephropathy demonstrated the strongest association with HRQoL impairment: 86% of affected patients reported problems in both mobility and pain/discomfort dimensions (P = 0.001 each), consistent with the substantial functional impact of renal disease on daily living activities. Lower socioeconomic status (income) was significantly associated with both EQ-5D-5L index (P = 0.024) and EQ-VAS (P = 0.003). This is congruent with a JEHP-published study demonstrating that lower education, income, and lack of insurance coverage were each independently associated with lower EQ-5D scores in population-based surveys.[22]

The modest inverse association between glycemic parameters (FBS, PPBS) and HRQoL scores in our correlation analysis is consistent with the established evidence that suboptimal metabolic control is associated with lower HRQoL.[5,7] Importantly, these glycemic associations are correlational and cannot be interpreted causally given the cross-sectional design. Future studies should employ longitudinal or interventional designs to assess whether improved glycemic control translates to improved HRQoL outcomes. Structured self-management education and counselling programmers have demonstrated improvements in self-reported quality of life outcomes in T2DM, as evidenced in a recent JEHP-published trial.[23] Similarly, lifestyle interventions have shown significant positive effects on HRQoL across randomized controlled trials, as confirmed in a JEHP meta-analysis.[24]

Limitations, strengths, and weaknesses

This study was restricted to a single UHTC in Coimbatore, limiting generalizability to rural populations or other regions of India. The cross-sectional design precludes causal inference. The study was conducted over a short duration (April–July 2025) without a healthy control group. Clinical data retrieved from hospital records may introduce information bias. Potential confounders—BMI, HbA1c, depression diagnosis, and lifestyle factors—were not fully controlled for in multivariable analyses, representing a key limitation. The primary strengths are the use of a licensed Tamil-language EQ-5D-5L version, consecutive sampling to minimize selection bias, and the provision of primary care-level HRQoL evidence from an underrepresented South Indian setting.

Conclusion

Among T2DM patients attending an urban primary care setting in South India, pain/discomfort and anxiety/depression are the most significantly impaired HRQoL dimensions. Microvascular complications—particularly nephropathy—longer disease duration, diabetes-related hospitalization, and lower socioeconomic status are important determinants of reduced HRQoL. These findings have direct implications for primary care policy: programmers targeting T2DM should integrate systematic screening for pain and psychosocial distress, and priorities complication prevention, structured patient education, and financial support mechanisms for low-income patients.

From a health policy perspective, these findings reinforce the need to strengthen the National Programmed for Prevention and Control of Cancer, Diabetes, Cardiovascular Diseases and Stroke (NPCDCS) to include patient-reported HRQoL as a monitoring indicator at urban primary care facilities. The EQ-5D-5L instrument demonstrates feasibility and validity as a patient-reported outcome measure in this setting and should be considered for integration into routine diabetes care protocols.

Suggestions for further research

Future studies should employ longitudinal or multicenter designs including rural and semi-urban populations to generate nationally representative data. Multivariable regression models adjusting for HbA1c, body mass index (BMI), depression, and lifestyle factors should be incorporated to identify independent predictors of HRQoL. Economic evaluations linking HRQoL indices to cost-of-illness analyses in T2DM would inform resource allocation for NCD programmers in India.

Study/Project ID

The study was approved by the Institutional Ethics Committee (IEC Approval Number: PSG/IHEC/2025/ APPR/EXP/063)

Artificial intelligence (AI) policy

Authors who use AI tools in the writing of a manuscript, production of images or graphical elements of the paper, or in the collection and analysis of data, must be transparent in disclosing in the Materials and Methods (or similar section) of the paper how the AI tool was used and which tool was used. Authors are fully responsible for the content of their manuscript, even those parts produced by an AI tool, and are thus liable for any breach of publication ethics. The primary investigator declares that no AI tools were used in the writing, image production, or data collection and analysis for this manuscript.

Abbreviations

T2DM: Type 2 Diabetes Mellitus; HRQoL: Health-Related Quality of Life; EQ-5D-5L: EuroQol Five Dimension Five Level; EQ-VAS: EuroQol Visual Analogue Scale; FBS: Fasting Blood Sugar; PPBS: Post-Prandial Blood Sugar; IHD Ischemic Heart Disease; SD: Standard Deviation; UHTC: Urban Health Training Centre; OPD: Outpatient Department; NPCDCS: National Programmed for Prevention and Control of Cancer, Diabetes, Cardiovascular Diseases and Stroke.

Author’s contributions

SS: Conceptualization, methodology, formal analysis, investigation, project administration, writing – original draft. RSK, MV and SLRS: Visualization, methodology and investigation. RN: Data analysis, visualization, project administration. All the author reviewed the final manuscript.

Availability of data and materials

Data has been manually collected by the author and analyzed using MS excel. All data available in the manuscript.

Conflicts of interest

None declared.

Funding Statement

No funding received.