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Clinical characteristics, treatment patterns, & outcomes of heart failure: A comparative analysis across age groups from the heart failure registry in India
For correspondence: Dr Prashant Mathur, Director, ICMR - National Centre for Disease Informatics and Research, Bengaluru 562 110, Karnataka, India e-mail: mathurp.hq@icmr.gov.in
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Received: ,
Accepted: ,
Abstract
Background & objectives
Heart failure is a major health burden globally. While the prevalence of heart failure is increasing, limited research has focused on the specific characteristics and outcomes of patients with heart failure belonging to different age groups in India. This study aimed to describe the clinical characteristics, treatment patterns and outcomes of patients with heart failure in India with a focus on comparing these aspects among young (16 to 40 yr), middle-aged (41-64 yr), and elderly (≥ 65 yr) individuals.
Methods
A multicentre, hospital-based study was conducted in five small- to medium-sized cities in India. Participants included admitted cases of heart failure between June 2018 and March 2022. Demographic and clinical information, including comorbidities, and data on aetiology, treatment, and outcomes, were collected using a standardised proforma. Statistical analyses were conducted to compare variables across age groups.
Results
Out of 6018 participants, 613 (10.2%) were young adults, 3207 (53.3%) were middle-aged, and 2198 (36.5%) belonged to the elderly age group. Most of the patients (>60%) were from rural areas. Ischemic heart disease (IHD) was the most common aetiology across all three age groups (52.4%, 75.1%, and 76.9%), and the 90-day mortalities for the three age groups were 12.6, 13.4 and 19 per cent, respectively. Young patients presented with milder symptoms, distinct aetiologies, and fewer comorbidities than older age groups. Treatment patterns varied across age groups. Young patients had longer hospital stays and higher in-hospital mortality rates. However, long-term mortality rates were higher among the older age groups.
Interpretation & conclusions
This study provides valuable insights into the clinical characteristics, treatment patterns and mortality rates of individuals with heart failure in India, particularly from rural areas. The findings highlight the need for tailored approaches for different age groups in the prevention and management of heart failure, with a special focus on the young and rural population.
Keywords
Age groups
heart failure
mortality rates
registry
young patients
Heart failure (HF) affects approximately 1-3 per cent of the global population, and the majority among them are older individuals1. It is estimated that there are 1.3 to 4.6 million people suffering from Heart failure in India. The available data from India reveals that heart failure patients are relatively younger (56-62 yr)2-7 and have worse prognosis (in-hospital mortality: 8.4-13.2%)5-6,8 compared to their counterparts in the West and other Asian countries (mean age: 60-78 yr and in-hospital mortality: 2.9-6.7%)9-12.
In the absence of regular national-level surveillance for cardiovascular diseases (CVD) in India, there is a scarcity of comparative data available regarding the clinical characteristics and outcomes of heart failure across various age groups. The available literature reported 21 per cent of individuals below 50 yr of age with heart failure and having a one-year mortality rate of 16 per cent4. Furthermore, it is essential to understand the variations in clinical presentation, underlying causes, and prognosis between younger and older individuals experiencing heart failure. Such understanding would be instrumental in devising targeted prevention and management approaches specific to heart failure in the young population.
To address this research gap, the Indian Council of Medical Research-National Centre for Disease Informatics & Research (ICMR-NCDIR), Bengaluru, Karnataka, established a heart failure registry to study the causes and patterns of care for heart failure. This paper aims to describe and compare the clinical characteristics and outcomes of hospitalised heart failure cases in different age groups.
Material & Methods
This observational study was undertaken by the ICMR-National Centre for Disease Informatics & Research (ICMR-NCDIR), Bengaluru, Karnataka, India. The study was approved by the ICMR-NCDIR Institutional Ethics Committee (IEC) and by the respective Institutional Ethics Committees of the participating centres.
Study design
This was a prospective observational multi-centre hospital-based study conducted in government medical colleges and hospitals located in five small- to medium-sized cities (population less than 1.5 million) located in different regions of India (Shimla, Ajmer, Bhubaneswar, Mysuru and Tirunelveli). All the consecutive cases of heart failure aged more than 16 years and admitted in the above hospitals between June 2018 to March 2022 were included in the study.
Study tools and data collection
A standardised proforma was designed for baseline and follow-up data collection. ICMR-NCDIR was the coordinating unit, which provided scientific and technical support for all the participating centres. Each participating centre had trained project staff for data abstraction and transmission. Once the treating physician diagnosed HF, the data abstraction was done and verified before entering the data into the online portal.
Demographic and clinical information were abstracted from the clinical records. Name, age, sex, locality (urban/rural) and education status were included as baseline demographic data. The details on family history (diabetes, hypertension, coronary artery disease, stroke, sudden death and cardiomyopathy), risk factors and co-morbidities [tobacco and/or alcohol consumption, obesity, diabetes, hypertension, anaemia, chronic kidney disease (CKD), chronic obstructive pulmonary disease (COPD), thyroid disorders etc.], underlying cardiovascular disease [ischemic heart disease(IHD), cardiomyopathy, rheumatic heart disease(RHD), non-rheumatic valvular heart disease (NRVHD), hypertensive heart disease, tachyarrhythmia, congenital heart diseases and infective myocarditis], signs, symptoms, vitals, diagnostic test results (biochemical tests, biomarkers and 2D Echogram), treatment, and outcome at discharge were included in the data extraction form.
All cases were followed up at 30 days, 90 days and 180 days from the date of admission. The follow up data were captured during the regular visit of patients to the hospital or by telephonic call. Vital status (alive or dead) was the outcome assessed at the end of 180 days.
Quality of the data was ensured through in-built validation checks in the software, regular quality checks and deleting duplicate cases using duplicate check software and onsite data validation during physical visits by the coordinating unit.
Statistical analysis
Age was categorised into three groups: Young (16 to 40 yr), middle-aged (41 to 64 yr) and elderly (≥65 yr). Data was analysed using IBM SPSS Statistics 27 (IBM Corp., Armonk, NY). Demographic and clinical characteristics were summarised as mean with standard deviation or median with interquartile range based on normality distribution for continuous variables. Categorical variables were presented as proportions. Comparison of independent variables across the age groups was carried out using ANOVA or Kruskal-Wallis test for continuous variables and Pearson’s Chi-square or Fisher’s exact or Yates continuity correction for categorical variables. All analyses were carried out with a significance level of P<0.05.
Results
Out of the 6018 participants admitted and registered with a diagnosis of heart failure, 613 (10.2 %) were young adults, 3207 (53.3%) were middle-aged, and 2198 (36.5%) belonged to the elderly age group. Across all age groups, most participants were male; however, at two specific centres, there was a higher representation of young females (Supplementary Table). Most of the cases came from rural areas and had received primary education (Table I).
| Variables | 16-40 yr | 41-64 yr | ≥ 65 yr | P value |
|---|---|---|---|---|
| Total cases, n (%) | 613 (10.2) | 3207 (53.3) | 2198 (36.5) | |
| Age in yr (mean±SD) | 33.1±6.2 | 54.2±6.4 | 71.8±5.9 | <0.001 |
| Gender, n (%) | ||||
| Male | 400 (65.3) | 2302 (71.8) | 1345 (61.2) | <0.001 |
| Female | 213 (34.7) | 905 (28.2) | 853 (38.8) | |
| Area of residence, n (%) | ||||
| Urban | 219 (35.7) | 1311 (40.9) | 845 (38.4) | 0.03 |
| Rural | 394 (64.3) | 1896 (59.1) | 1353 (61.6) | |
| Education, n (%) | ||||
| Illiterate | 78 (12.7) | 1065 (33.2) | 1097 (49.9) | <0.001 |
| Primary | 282 (46) | 1378 (43) | 748 (34) | |
| Secondary | 169 (27.6) | 565 (17.7) | 239 (10.9) | |
| Graduate and higher | 84 (13.7) | 197 (6.1) | 114 (5.2) | |
| Family history, n (%) | ||||
| Diabetes | 93 (15.2) | 653 (20.4) | 300 (13.6) | <0.001 |
| Hypertension | 88 (14.4) | 426 (13.3) | 203 (9.2) | <0.001 |
| Coronary artery disease | 60 (9.8) | 247 (7.7) | 106 (4.8) | <0.001 |
| Stroke | 12 (2) | 103 (3.2) | 55 (2.5) | 0.12 |
| Sudden death | 14 (2.3) | 75 (2.3) | 34 (1.5) | 0.12 |
| Cardiomyopathy | 8 (1.3) | 33 (1) | 28 (1.3) | 0.61 |
| No significant family history | 422 (68.8) | 2179 (67.9) | 1706 (77.6) | <0.001 |
| Risk factors | ||||
| Tobacco use, n (%) | 256 (41.8) | 1642 (51.2) | 947 (43.1) | <0.001 |
| Alcohol use, n (%) | 232 (37.8) | 1138 (35.5) | 521 (23.7) | <0.001 |
| BMI(kg/m2); mean±SD | 21.4±18.3 | 22.2±17.8 | 21.4±23.5 | 0.36 |
| Comorbidities, n (%) | ||||
| Diabetes mellitus | 98 (16) | 1480 (46.1) | 1046 (47.6) | <0.001 |
| Hypertension | 183 (29.9) | 1558 (48.6) | 1284 (58.4) | <0.001 |
| Anaemia | 120 (19.6) | 550 (17.1) | 527 (24) | <0.001 |
| Chronic kidney disease (CKD) | 38 (6.2) | 243 (7.6) | 253 (11.5) | <0.001 |
| Chronic obstructive pulmonary disease (COPD) | 34 (5.5) | 315 (9.8) | 316 (14.4) | <0.001 |
| Thyroid disorders | 48 (7.8) | 171 (5.3) | 153 (7) | 0.01 |
| Sleep apnoea | 64 (10.4) | 239 (7.5) | 176 (8) | 0.04 |
| No comorbidity | 107 (17.5) | 334 (10.4) | 156 (7.1) | <0.001 |
SD, standard deviation; BMI, body mass index
A significant proportion of participants had no family history. The younger individuals had a significant family history of hypertension (14.4%) and coronary artery disease (9.8%) compared to other age groups. The prevalence of tobacco consumption was high among the middle-aged (51.2%), and alcohol consumption was high in young individuals (37.8%). Diabetes mellitus, hypertension, anaemia, COPD, and CKD were the common comorbidities among the elderly age group, whereas 17.5 per cent of the young had no comorbidity (Table I). IHD was the most common aetiology for Heart Failure across all age groups, more among the elderly age group. A significantly large proportion of young cases had cardiomyopathy and RHD compared to middle-aged and elderly individuals. One-third of young individuals presented with grade I or II under the New York Heart Association (NYHA) classification system. But the majority (64.2%) presented with NYHA grade III or IV.
Almost one in seven (14.2%) young individuals with heart failure required intensive care, whereas middle-aged individuals had a slightly lower admission rate to the intensive care unit at 12.8 per cent. N-terminal Prohormone B-type natriuretic peptide (NT-proBNP) was measured in 1831 cases (30.4%), and BNP was measured in 667 (11.1%). However, no case had both BNP and NT-proBNP tested simultaneously. The median NT-proBNP value increased with age, whereas the mean Left Ventricular Ejection Fraction (LVEF) decreased. Heart failure with reduced ejection fraction (HFrEF) was more common in the middle-age group (60.5%), whereas heart failure with preserved ejection fraction (HFpEF) was more prevalent in young individuals (24.6%) and declined with age (Table II).
| Clinical characteristics | 16-40 yr | 41-64 yr | ≥ 65 yr | P value |
|---|---|---|---|---|
| Aetiological factors, n (%) | ||||
| Ischaemic heart disease (IHD) | 321 (52.4) | 2408 (75.1) | 1691 (76.9) | <0.001 |
| Cardiomyopathy | 190 (31) | 981 (30.6) | 624 (28.4) | 0.18 |
| Rheumatic heart disease (RHD) | 122 (19.9) | 237 (7.4) | 66 (3) | <0.001 |
| Non-rheumatic valvular heart disease (NRVHD) | 20 (3.3) | 56 (1.7) | 51 (2.3) | 0.04 |
| Hypertensive heart disease | 5 (0.8) | 71 (2.2) | 65 (3) | 0.006 |
| Tachyarrhythmias | 14 (2.3) | 81 (2.5) | 53 (2.4) | 0.96 |
| Congenital heart disease | 22 (3.6) | 14 (0.4) | 9 (0.4) | <0.001 |
| Infective myocarditis | 2 (0.3) | 2 (0.1) | 1 (0) | 0.1 |
| NYHA classification, n (%) | ||||
| I | 27 (4.4) | 88 (2.7) | 47 (2.1) | <0.001 |
| II | 168 (27.4) | 823 (25.7) | 462 (21) | |
| III | 331 (54) | 1759 (54.8) | 1298 (59.1) | |
| IV | 87 (14.2) | 537 (16.7) | 391 (17.8) | |
| Type of admission, n (%) | ||||
| ICU/CCU | 87 (14.2) | 410 (12.8) | 403 (18.3) | <0.001 |
| Other in-patient | 526 (85.8) | 2797 (87.2) | 1795 (81.7) | |
| Blood pressure at admission | ||||
| High BP (SBP ≥140 & DBP ≥90) | 154 (25.2) | 1083 (33.8) | 798 (36.3) | < 0.001 |
| Low BP (SBP ≤ 100 & DBP ≤60) | 194 (31.6) | 785 (24.5) | 531 (24.2) | |
| Normal (SBP 101-139 & DBP 61-89) | 265 (43.2) | 1339 (41.7) | 869 (39.5) | |
| Systolic BP (mmHg), mean±SD | 116.8±24 | 123.1±26.4 | 124.8±26.5 | <0.001 |
| Diastolic BP (mmHg), mean±SD | 76.5±15.2 | 78.6±14.9 | 78.4±14.9 | 0.005 |
| Biomarkers | ||||
| BNP (pg/ml), Median (IQR) |
596.5 (99-1094) |
429 (197-1190) |
475.2 (402-1026) |
0.88 |
| NT- proBNP (pg/ml), Median (IQR) |
3747 (1500-10212) |
5988 (1767-14129) |
6816 (1608-17444) |
0.07 |
| LVEF%, mean±SD | 40.6±13.6 | 37.6±11.4 | 37.4±10.8 | <0.001 |
| Type of heart failure, n (%) | ||||
| HFrEF (LVEF <40%) | 319 | 1939 (60.5) | 1323 (60.2) | <0.001 |
| HFmrEF (LVEF 40-49%) | 127 (20.7) | 743 (23.2) | 562 (25.6) | |
| HFpEF (LVEF ≥ 50%) | 151 (24.6) | 464 (14.5) | 274 (12.5) |
NYHA, New York heart association; ICU, intensive care unit; CCU, cardiac care unit; BP, blood pressure; BNP, brain natriuretic peptide; NT-proBNP, N-terminal pro b-type natriuretic peptide; IQR, interquartile range; LVEF, left ventricular ejection fraction; HFrEF, heart failure with reduced ejection fraction; HFmrEF, heart failure with mildly reduced ejection fraction; HFpEF, heart failure with preserved ejection fraction
Table III provides an overview of the treatment provided for heart failure cases during hospitalisation, revealing that a significant proportion of young individuals received loop diuretics, although at a lower rate than the middle-aged and elderly groups. (78.3 vs. 79.8% and 85.7%, respectively; P<0.001). Beta blockers, Angiotensin-converting enzyme inhibitors/ Angiotensin II receptor blockers (ACEI/ARB), and mineralocorticoid Receptor Antagonist (MRA) were the other common drugs given across all age groups. Very few cases among the middle-aged and elderly age group received cardiac resynchronisation therapy and Implantable defibrillators.
| Treatment | 16-40 yr, n (%) | 41-64 yr, n (%) | ≥ 65 yr, n (%) | P value |
|---|---|---|---|---|
| Loop diuretics | 480 (78.3) | 2558 (79.8) | 1883 (85.7) | <0.001 |
| β Blockers | 366 (59.7) | 1923 (60) | 1177 (53.5) | <0.001 |
| ACEI/ARB | 304 (49.6) | 1826 (56.9) | 1173 (53.4) | <0.001 |
| Ivabradine/Hydralazine | 101 (16.5) | 494 (15.4) | 355 (16.2) | 0.67 |
| Mineralocorticoid receptor antagonist | 328 (53.5) | 1583 (49.4) | 1153 (52.5) | 0.03 |
| Angiotensin receptor-neprilysin inhibitor | 36 (5.9) | 222 (6.9) | 164 (7.5) | 0.39 |
| Digoxin | 152 (24.8) | 557 (17.4) | 361 (16.4) | <0.001 |
| Statins | 324 (52.9) | 2483 (77.4) | 1728 (78.6) | <0.001 |
| Nitrates | 166 (27.1) | 1140 (35.5) | 834 (37.9) | <0.001 |
| Anticoagulants | 242 (39.5) | 1578 (49.2) | 1000 (45.5) | <0.001 |
| Inotropic support | 89 (14.5) | 358 (11.2) | 284 (12.9) | 0.03 |
| Cardiac resynchronisation therapy | 0 | 7 (0.2) | 3 (0.1) | 0.67 |
| Implantable defibrillator | 0 | 2 (0.1) | 3 (0.1) | 0.66 |
| Pacemaker | 0 | 4 (0.1) | 9 (0.4) | 0.07 |
ACEI, angiotensin converting enzyme inhibitor; ARB, angiotensin receptor blockers
Young individuals had a high [6 (4-10)] median duration of hospital stay and in-hospital mortality (6.2%) compared to other age groups (5% and 5.2%). However, the 30-day, 90-day, and 180-day mortality was significantly higher among the older age group (Table IV).
| Outcomes | 16-40 yr | 41-64 yr | ≥ 65 yr | P value |
|---|---|---|---|---|
| Duration of stay in hospital, median (IQR) days | 6 (4-10) | 5 (3-9) | 5 (3-8) | <0.001 |
| In-hospital mortality, n (%) | 38 (6.2) | 161 (5) | 115 (5.2) | 0.46 |
| 30-day mortality, n (%) | 53 (8.6) | 284 (8.9) | 266 (12.1) | <0.001 |
| 90-day mortality, n (%) | 77 (12.6) | 431 (13.4) | 418 (19) | <0.001 |
| 180-day mortality, n (%) | 90 (14.7) | 531 (16.6) | 524 (23.8) | <0.001 |
Discussion
The study provides an overview of the clinical characteristics, treatment during hospitalisation, and mortality patterns of individuals with heart failure across different age categories: young, middle-aged, and elderly. The younger individuals had less severe clinical presentation and less significant comorbidities than other age groups. While most patients in other age groups had ischemic aetiology, younger individuals in this study had distinct aetiologies at a greater proportion. Compared to older age groups, the young had longer hospital stays and higher in-hospital mortality. But the long-term mortality was high among older age groups.
The proportion of younger individuals in this study was high compared to other studies done in Western countries, where the younger population contributed 1 to 6 per cent of cases13-18. However, studies done in India and other Asian countries4,19 had findings consistent with our results. The proportion of female patients was higher in younger age group than in the group of middle-aged, but lower when compared to elderly individuals. The Meta-analysis Global Group in the Chronic Heart Failure (MAGGIC) study15 and a study conducted in Montefiore Medical Centre, USA14 had similar observations. Most of the patients in our study were from rural areas and had minimum education across all age groups. This is because the registries were established in small to medium-sized cities, catering largely to the rural population.
Tobacco consumption was high among the middle-aged, but alcohol use was high in the younger individuals. Other studies, like the CHARM programme13 and a pooled population-based cohort study18, reported higher smoking rates in the younger population. Since the data on tobacco and alcohol were abstracted from clinical records, there is a higher probability that the physicians could have recorded this information sub-optimally. Hypertension and diabetes were the most common comorbidities, and across all age groups but 17.5 per cent of young individuals presented with no comorbidities. Though IHD was the most common aetiology for HF in the younger group, the proportion was significantly less compared to other age groups. The proportion of other CVDs, like cardiomyopathies, RHD, NRVHD, and congenital heart disease, was higher among the young individuals. In other studies, the proportion of IHD among young ranged from 14-21 per cent, whereas cardiomyopathies ranged from 20-60 per cent13-15,17.
In this study, 32 per cent of young individuals presented with NYHA I and II, had lower NT-proBNP values and a high mean LVEF per cent compared to other age groups. The proportion of young individuals having heart failure with preserved ejection fraction (HFpEF) was significantly high. These results deviated from the findings of other studies done on young individuals, as they had included hospitalised, symptomatic patients with acute heart failure13-14,16. In our study, treatment approaches varied across age groups, with diuretics being commonly prescribed to all age groups, and beta blockers and ACEI/ARBs being less prescribed, especially among the young. More than three-fourths of patients across all age groups received diuretics, and only 58 per cent received beta blockers and 54 per cent received ACEI/ARBs during hospitalisation. Other studies done in India for all age groups show similar prescription of diuretics, but the proportion of beta blockers (53% and 82%) and ACEI/ARBs (37% and 82%) varies between the studies4,20. A small percentage of older individuals received treatments beyond medical management, such as Cardiac Resynchronisation Therapy, Implantable Defibrillators, and Pacemakers. None of the younger participants in the study received these specific treatments.
The median duration of stay for all age groups was lower compared to the Candesartan in Heart Failure Assessment of Reduction in Mortality and Morbidity (CHARM) programme13, whereas a similar result was found in the Malaysian12 and Trivandrum registries20. The 180-day mortality for younger individuals was high in our study (14.7%) compared to the PROTECT Trial (9.9%)16, but the overall mortality was similar to the Trivandrum registry20. The trend of survival probability decreasing as age progresses was similar in other studies having long-term follow up13-15. Our findings revealed that young individuals experienced higher ICU admission (14.2%), longer hospital stay (median 6 days) and higher in-hospital mortality rate (6.2%), suggesting more severe disease at the time of admission. However, the long-term mortality rates were higher among the older age groups, indicating that age remains a significant determinant of poor outcomes in heart failure.
While most studies on heart failure among the Indian population have focused on metropolitan areas, which primarily reflect an urban context, our study uniquely examines heart failure in small to medium-sized cities, providing valuable insights into the rural population. However, it is important to acknowledge that relying solely on data abstraction from clinical records presents a limitation, as incomplete documentation of risk factors and comorbidities in the case records may have resulted in the loss of valuable information. Furthermore, the utilisation of more precise diagnostic techniques like Cardiac Magnetic Resonance Imaging (MRI) or Positron Emission Tomography (PET) scans was limited within our study.
A higher proportion of young individuals with heart failure in India compared to Western countries was highlighted in this study, emphasising the need for addressing heart failure in the young Indian population. The study emphasises the need to enhance both primary and secondary prevention measures for CVDs, especially for IHD, as this is an important aetiology for heart failure across all age groups. The study also highlighted the importance of early identification and management of cardiomyopathies and RHD among the younger population. Even after seeking treatment at a tertiary care centre, a concerning trend of increased mortality rates persisted. The premature death of individuals in their economically productive age group not only affects families but also has broader implications for the country’s well-being.
Overall, this study highlights the unique clinical characteristics and outcomes of heart failure patients across different age groups in India, with a particular focus on younger individuals. While IHD remains the leading cause across all age groups, a significantly higher proportion of young patients presented with cardiomyopathies and RHD, and experienced higher in-hospital mortality. These findings underscore the need for tailored prevention and management strategies specifically for young heart failure patients. Addressing treatment gaps, such as the lower use of Cardiac Resynchronisation Therapy, Implantable Defibrillators, and Pacemakers, is crucial. The study offers valuable insights into heart failure in India’s rural and semi-urban populations, emphasising the need for improved care and targeted interventions for the young population.
Acknowledgment
Authors acknowledge the study participants for their participation, the Co-Principal Investigators from the five study sites, registry staff involved in data abstraction and entry, project staff and collaborating institutions for their support during conduct of the study.
Financial support & sponsorship
Study received funding support by intra-mural grant (5/13/13/2017/DHR/NCDIR/NCD-III) of ICMR-National Centre for Disease Informatics and Research, Bengaluru.
Conflicts of Interest
None.
Use of Artificial Intelligence (AI)-Assisted Technology for manuscript preparation
The authors confirm that there was no use of AI-assisted technology for assisting in the writing of the manuscript and no images were manipulated using AI.
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