European Journal of Cardiovascular Medicine

Chronic Kidney Disease (CKD): A Rising Health Challenge in Andhra Pradesh. Chronic kidney disease (CKD) represents a major global health concern, with its increasing prevalence creating substantial challenges for healthcare systems worldwide. In Andhra Pradesh, a southern state in India, CKD is becoming an escalating public health issue. Gaining a comprehensive understanding of the clinical presentation and the etiological factors influencing CKD in this region is crucial for enhancing preventive and management strategies. This study examines the clinical spectrum and underlying causes of CKD in patients attending a tertiary care center in Andhra Pradesh, offering deeper insights into the complexities of this chronic condition. ^[1]

Clinical Spectrum of CKD: CKD is a progressive, irreversible disorder characterized by the gradual decline of renal function over time. Patients typically move through five stages of disease progression, with the final stage requiring renal replacement therapy, such as dialysis or kidney transplantation. Although the clinical features of CKD may vary among individuals, several common manifestations are frequently observed:

1. Hypertension: High blood pressure is a prevalent feature of CKD and often precedes its diagnosis. It not only accelerates the progression of kidney damage but also elevates the risk for cardiovascular diseases.
2. Proteinuria: The abnormal presence of protein in the urine, termed proteinuria, serves as an early marker of kidney injury and reflects disease severity.
3. Reduced Glomerular Filtration Rate (GFR): A decline in GFR, an essential measure of renal function, is a key diagnostic indicator of CKD.
4. Anemia: The disease often leads to reduced production of erythropoietin, a hormone vital for red blood cell generation, resulting in anemia.
5. Metabolic Disturbances: Electrolyte imbalances, including alterations in sodium, potassium, calcium, and phosphate levels, are common in patients with CKD. ^[2,3]

Etiological Factors Contributing to CKD: The underlying causes of CKD are diverse and can differ significantly by region. In Andhra Pradesh, several important factors are implicated:

1. Diabetes Mellitus: Diabetes remains the leading cause of CKD both globally and within Andhra Pradesh. Persistent hyperglycemia damages the kidney's microvasculature, eventually impairing renal function.
2. Hypertension: Chronic elevated blood pressure is a major risk factor for CKD. The coexistence of diabetes and hypertension can significantly worsen kidney injury.
3. Infections: Chronic or recurrent infections, such as urinary tract infections and pyelonephritis, can predispose individuals to CKD if not properly managed.
4. Environmental Factors: In specific regions of Andhra Pradesh, environmental exposures, particularly high levels of fluoride in drinking water, have been associated with kidney dysfunction. Prolonged exposure to such substances can contribute to renal impairment over time.
5. Hereditary and Genetic Influences: Certain forms of CKD are inherited, with genetic factors playing a significant role in disease susceptibility and progression.
6. Medication and Toxin Exposure: The use of nephrotoxic medications, as well as exposure to environmental toxins and heavy metals, are notable contributors. In agricultural communities, pesticide exposure presents a particular concern.
7. Lifestyle Factors: Risk behaviors such as tobacco use, excessive alcohol intake, and diets rich in salt and processed foods are linked to an increased risk of CKD development. ^[4]

Study Objectives:

This study was conducted to evaluate the clinical profile of CKD patients attending Government Medical College, Kadapa, Andhra Pradesh. Specific objectives included identifying the underlying etiologies of CKD, assessing associated comorbid conditions, and examining the clinico-hematological correlation between risk factors and complications in individuals affected by chronic kidney disease.

Study design: Prospective observational study.

Study period: 1 year.

Place of study: Department of General Medicine, Government General Hospital, Kadapa.

Source of data: OPD and IPD admissions in General Medicine Department (GMC), GGH Kadapa.

Sample size: 100 patients

Sample size calculation: 4pq/d² where p is prevalence 100-p is d, which is allowable error (5% to 20%)

Inclusion criteria:

1.       Patients with Chronic Kidney Disease as defined by National Kidney Foundation (NKF) kidney disease: Improving Global Outcome (KDIGO) 2012 clinical practice guidelines

2.       Patients with Age > 18 years

Exclusion criteria:

1.       Age <18 years

2.       Patients who has not given consent

Study method: Patients presenting to the Department of General Medicine were evaluated through a structured questionnaire, followed by a comprehensive history-taking and physical examination. Key clinical parameters recorded included a history of diabetes mellitus, hypertension, smoking habits, and alcohol consumption. Vital signs and systemic examination findings were documented. Relevant investigations were carried out, including hemoglobin levels, liver function tests, routine urine analysis, renal function tests, serum sodium, serum potassium, abdominal ultrasonography (USG), arterial pH, partial pressure of carbon dioxide (pCO₂), bicarbonate levels, and calculation of the anion gap. The probable etiology of CKD was determined based on clinical and investigative findings, and the frequency distribution of different etiologies within the study population was analyzed. Patients were subsequently followed up either via telephone communication or during their scheduled revisit to the hospital.

Statistical analysis: The information gathered from all selected cases was systematically recorded in a master chart. Data analysis was performed using statistical software. Descriptive statistics, including mean and standard deviation, were calculated, and the p-value was determined to assess the significance of the findings.

TABLE 1: SOCIODEMOGRAPHIC DETAILS OF THE STUDY PARTICIPANTS

The majority (39%) are aged 31-50, indicating a middle-aged working population. 31% are 61-70, suggesting a significant elderly group. Only 10% are in 51-60, 71-80, and >80 each, showing fewer very old and late-middle-aged individuals. Male dominance (66%), possibly reflecting occupational or societal biases in the surveyed group. Females (34%) are underrepresented. Farmers (40%) and laborers (39%) form the bulk, aligning with rural residency (84%). Drivers (10%) and unemployed (11%) are minorities, suggesting most are engaged in manual labor. 62% are below the poverty line (BPL), indicating economic hardship for most. 38% above the poverty line (APL) suggests a smaller, economically stable group. Rural predominance (84%), consistent with farming/laborer occupations. Urban (16%) is a small fraction, possibly indicating limited urban outreach in the survey. Groundwater (65%) is the primary source, which may raise concerns about water quality. Filtered water (35%) is used by a third, suggesting some access to safer water. Non-vegetarian (80%) is the majority, possibly linked to rural occupations requiring high protein. Vegetarians (20%) are a smaller but notable group.

TABLE 2: FREQUENCIES OF THE STUDY PARTICIPANTS WITH RESPECT TO DIFFERENT ETIOLOGICAL FACTORS OF CKD

42% smoke, while 58% do not. Smoking is a significant risk factor for kidney disease, and this group may need targeted cessation programs. 35% consume alcohol, while 65% do not. Alcohol can contribute to hypertension and kidney damage, but the majority abstain. 69% are diabetic, which is alarmingly high. Diabetes is a leading cause of chronic kidney disease (CKD), explaining the high CKD staging in this population. 56% are hypertensive, another major CKD risk factor. Linked to diabetes, poor diet, and possibly high salt intake. 41% use analgesics regularly, which can harm kidneys if overused. 59% avoid them, which is positive for kidney health. 81% have contracted kidneys, indicating advanced kidney damage (common in late-stage CKD). Only 12% have normal kidney size, suggesting early or well-managed cases. 7% have enlarged kidneys, possibly due to obstruction or other conditions. Stage 3B (37%) and Stage 5 (29%) dominate, showing severe kidney dysfunction in most patients. Stage 4 (19%) also indicates progressive disease. Only 12% are in Stage 2 (mild CKD), and 3% are in Stage 3A—highlighting late diagnosis or rapid progression.

Table 4: Association of different sociodemographic parameters with Stages of CKD

Older age groups (especially >60 years) show a higher prevalence of advanced CKD (Stages 4 & 5), suggesting age is a significant risk factor for CKD progression. Males have a higher prevalence of advanced CKD compared to females, indicating possible gender-based differences in CKD risk (e.g., lifestyle, occupational hazards, or biological factors). Farmers and laborers have higher CKD progression, possibly due to dehydration, pesticide exposure, or strenuous work. Unemployed individuals were only in Stage 5, possibly due to poor healthcare access or comorbidities. Although BPL individuals have more CKD cases, the p-value is not significant, meaning economic status may not be a strong independent predictor of CKD stage in this study.

Rural populations have significantly higher CKD prevalence, possibly due to poor water quality, agricultural chemical exposure, or limited healthcare access. Groundwater users have higher CKD progression, suggesting contaminants (heavy metals, fluoride, etc.) may contribute to CKD. A non-vegetarian diet is strongly associated with CKD progression, possibly due to high protein intake, processed meat, or associated lifestyle factors.

Table 5: Association of different etiologic factors and investigations with Stages of CKD

Smoking is significantly associated with early-to-moderate CKD (stages 3A-4). Non-smokers have a higher prevalence in Stage 5, suggesting other factors (e.g., diabetes, hypertension) may drive late-stage CKD. Alcohol use is strongly linked to progressive CKD (Stages 3A-5). Non-alcoholics are more common in Stage 2 (early CKD) but also present in late stages, indicating alcohol exacerbates kidney damage. Diabetes is a major driver of CKD progression, with most cases in advanced stages (3B-5). Non-diabetics are rare, suggesting diabetes is a primary risk factor in this population. Hypertension is strongly associated with late-stage CKD (stages 4-5). Non-hypertensive individuals are more common in early stages (2-3B), but hypertension dramatically increases the risk of kidney failure (Stage 5). Analgesic use is linked to early-moderate CKD (Stages 2-3B) but not Stage 4, suggesting acute or intermittent damage. Non-users dominate Stage 4, implying other factors (e.g., diabetes, hypertension) drive late-stage CKD. Contracted kidneys correlate with advanced CKD (stages 4-5), indicating chronic scarring and irreversible damage. Enlarged kidneys are seen only in Stage 2, suggesting early compensatory hypertrophy (e.g., diabetic nephropathy). Normal-sized kidneys in Stage 3B may indicate early structural preservation despite functional decline.

Table 6: Association of different investigations with Stages of CKD

Higher albuminuria levels strongly correlate with advanced CKD (stages 3B-5). 1+ albuminuria is limited to Stage 2, suggesting early kidney damage. Clinical Implication: Albuminuria is a key marker of CKD progression; severe proteinuria (3+) indicates a poor renal prognosis. Urea rises sharply in late-stage CKD, reflecting declining glomerular filtration rate (GFR). Stage 5 patients show the highest urea levels, indicating severe uremia. Creatinine is a definitive marker of CKD severity. Stage 5 patients have critically high creatinine, necessitating dialysis or transplant. Hyponatremia is common in early and end-stage CKD, likely due to impaired water excretion. Hypernatremia is rare but concerning, possibly indicating dehydration or sodium retention. Hypokalemia in Stage 3B suggests tubular dysfunction or diuretic use. Hyperkalemia in Stage 5 reflects severe renal failure (life-threatening without intervention). Hypocalcemia is prevalent in CKD, likely due to vitamin D deficiency and hyperphosphatemia. Normal calcium in late stages may indicate secondary hyperparathyroidism or supplementation.  Anemia worsens with CKD progression, peaking in Stage 5 due to erythropoietin deficiency. Clinical Implication: Early anemia correction (iron/EPO therapy) may slow CKD progression.

This research investigated the demographic, etiological, and clinical characteristics of patients with chronic kidney disease (CKD) within a hospital environment and assessed the attributes of individuals hospitalized due to CKD. It encompassed a review of patients' age, gender, geographical region, and socioeconomic background. Moreover, the study sought to pinpoint the root causes of CKD among these individuals, including diabetes, hypertension, and other contributing factors. Additionally, the research analyzed the clinical manifestations of CKD, encompassing symptoms, lab results, and the extent of kidney damage.

The majority (39%) are aged 31-50, indicating a middle-aged working population. 31% are 61-70, suggesting a significant elderly group. Only 10% are in 51-60, 71-80, and >80 each, showing fewer very old and late-middle-aged individuals. Male dominance (66%), possibly reflecting occupational or societal biases in the surveyed group. Females (34%) are underrepresented. Farmers (40%) and laborers (39%) form the bulk, aligning with rural residency (84%). Drivers (10%) and unemployed (11%) are minorities, suggesting most are engaged in manual labor. 62% are below the poverty line (BPL), indicating economic hardship for most. 38% above the poverty line (APL) suggests a smaller, economically stable group. Rural predominance (84%), consistent with farming/laborer occupations. Urban (16%) is a small fraction, possibly indicating limited urban outreach in the survey. Groundwater (65%) is the primary source, which may raise concerns about water quality. Filtered water (35%) is used by a third, suggesting some access to safer water. Non-vegetarian (80%) is the majority, possibly linked to rural occupations requiring high protein. Vegetarians (20%) are a smaller but notable group.

In their investigation, Modi et al. [5] discovered that the average age was 47 years. As people age, the prevalence of CKD rises. [6] Males outnumbered females in our study, which was consistent with previous research. [7,8] According to Chaudhari et al. [9], the most prevalent causes of chronic kidney disease were chronic glomerulonephritis (10.0%), hypertensive nephropathy (20.0%), and diabetic nephropathy (32.0%). According to Sathyan et al. [10], the most prevalent causes of CKD were diabetic nephropathy (22.0%) and CGN (51.0%). In their research, Jha et al. [11] discovered that the most prevalent causes of chronic kidney disease were hypertensive nephropathy (12.8%) and diabetic nephropathy (31.2%). According to Parsi et al.12, the most prevalent etiological agents for chronic kidney disease (CKD) were diabetes (40.0%) and hypertension (32.0%).

Based on serum creatinine estimates, the prevalence of CKD in the southern region of New Delhi¹³ was recorded at 0.79 percent, while the prevalence of reduced Modification of Diet in Renal Disease-GFR stood at 4.2% within the north Indian population. ¹⁴ A different study carried out in rural southern India revealed that the prevalence of CKD was 6.3%, and the prevalence of reduced modification of diet in renal disease-GFR was 4.35%. [15] 42% smoke, while 58% do not. Smoking is a significant risk factor for kidney disease, and this group may need targeted cessation programs. 35% consume alcohol, while 65% do not. Alcohol can contribute to hypertension and kidney damage, but the majority abstain. 69% are diabetic, which is alarmingly high. Diabetes is a leading cause of chronic kidney disease (CKD), explaining the high CKD staging in this population. 56% are hypertensive, another major CKD risk factor. Linked to diabetes, poor diet, and possibly high salt intake. 41% use analgesics regularly, which can harm kidneys if overused. 59% avoid them, which is positive for kidney health. 81% have contracted kidneys, indicating advanced kidney damage (common in late-stage CKD). Only 12% have normal kidney size, suggesting early or well-managed cases. 7% have enlarged kidneys, possibly due to obstruction or other conditions. Stage 3B (37%) and Stage 5 (29%) dominate, showing severe kidney dysfunction in most patients. Stage 4 (19%) also indicates progressive disease. Only 12% are in Stage 2 (mild CKD), and 3% are in Stage 3A—highlighting late diagnosis or rapid progression.

We observed a greater percentage of tobacco users, a potentially changeable risk factor for chronic kidney disease (CKD) [16], compared to the Chronic Renal Insufficiency Cohort (CRIC), CKD-JAC, and German CKD (GCKD) studies [17-19]. The use of tobacco, particularly in smokeless forms, is a deeply rooted cultural tradition in various regions of India [20]. The Chinese Cohort Study of CKD (C-STRIDE) found an even higher rate of tobacco usage, reported at 38.2% [21].  Smoking is significantly associated with early-to-moderate CKD (stages 3A-4). Non-smokers have a higher prevalence in Stage 5, suggesting other factors (e.g., diabetes, hypertension) may drive late-stage CKD. Alcohol use is strongly linked to progressive CKD (Stages 3A-5). Non-alcoholics are more common in Stage 2 (early CKD) but also present in late stages, indicating alcohol exacerbates kidney damage. Diabetes is a major driver of CKD progression, with most cases in advanced stages (3B-5). Non-diabetics are rare, suggesting diabetes is a primary risk factor in this population. Hypertension is strongly associated with late-stage CKD (stages 4-5). Non-hypertensive individuals are more common in early stages (2-3B), but hypertension dramatically increases the risk of kidney failure (Stage 5). Analgesic use is linked to early-moderate CKD (Stages 2-3B) but not Stage 4, suggesting acute or intermittent damage. Non-users dominate Stage 4, implying other factors (e.g., diabetes, hypertension) drive late-stage CKD. Contracted kidneys correlate with advanced CKD (stages 4-5), indicating chronic scarring and irreversible damage. Enlarged kidneys are seen only in Stage 2, suggesting early compensatory hypertrophy (e.g., diabetic nephropathy). Normal-sized kidneys in Stage 3B may indicate early structural preservation despite functional decline.

Higher albuminuria levels strongly correlate with advanced CKD (stages 3B-5). 1+ albuminuria is limited to Stage 2, suggesting early kidney damage. Clinical Implication: Albuminuria is a key marker of CKD progression; severe proteinuria (3+) indicates a poor renal prognosis. Urea rises sharply in late-stage CKD, reflecting declining glomerular filtration rate (GFR). Stage 5 patients show the highest urea levels, indicating severe uremia. Creatinine is a definitive marker of CKD severity. Stage 5 patients have critically high creatinine, necessitating dialysis or transplant. Hyponatremia is common in early and end-stage CKD, likely due to impaired water excretion. Hypernatremia is rare but concerning, possibly indicating dehydration or sodium retention. Hypokalemia in Stage 3B suggests tubular dysfunction or diuretic use. Hyperkalemia in Stage 5 reflects severe renal failure (life-threatening without intervention). Hypocalcemia is prevalent in CKD, likely due to vitamin D deficiency and hyperphosphatemia. Normal calcium in late stages may indicate secondary hyperparathyroidism or supplementation. Anemia worsens with CKD progression, peaking in Stage 5 due to erythropoietin deficiency. Clinical Implication: Early anemia correction (iron/EPO therapy) may slow CKD progression.

CKD was most frequently caused by diabetes (25%). The fact that CIN became the second most prevalent, after CKDu, was a significant discovery. DKD was identified as the etiology in 31% of cases, followed by CKDu at roughly 19% and CGN at 14%, according to the 2012 Indian CKD Registry report [22]. The demographic dispersion of India is reflected in the fact that nearly two-thirds of the ICKD participants were from rural areas. Participants from rural and urban areas differed in a few ways. Participants from rural areas were less educated, earned less money, and had less insurance; were more likely to labor by hand; and were exposed to more dangerous workplace conditions. In addition, participants in rural areas reported greater levels of tobacco use and lower levels of self-reported physical activity.

In their evaluation of 5718 CKD patients, Manjuri Sharma et al. (23) discovered that diabetes mellitus was the most common cause (42.2%), followed by chronic obstructive uropathy (6.9%), chronic interstitial nephritis (3.6%), glomerulonephritis (21.4%), hypertension (19.5%), and autosomal dominant polycystic kidney disease (1.5%). After diabetic nephropathy (31%), this group was shown to be the second most common cause of chronic kidney disease (16%) in the Registry report, which included data on 52,273 patients. Because CKD is asymptomatic, it is often not identified until it has advanced, which leads to missed preventative chances. Early detection and treatment of CKD may prevent or delay the progression of renal failure or other unfavorable outcomes. Dialysis and renal transplantation are part of the traditional strategy to managing chronic kidney disease (CKD); however, most people cannot afford them for financial reasons. Therefore, it is necessary to investigate a safe and alternative therapy that can assist in delaying the need for a kidney transplant and lessening the need for dialysis.

This study highlights chronic kidney disease (CKD) as a major health issue in Andhra Pradesh, driven primarily by diabetes (69%) and hypertension (56%). Most patients were middle-aged, rural, and economically disadvantaged, with late-stage diagnosis (66% in Stages 3B–5). Key risk factors included smoking, alcohol use, and groundwater consumption, while contracted kidneys (81%) and severe albuminuria indicated advanced disease.  Urgent action is needed—early screening, better diabetes/hypertension control, and safer water access—to reduce CKD progression in high-risk populations. 

Recommendation:

This study underscores CKD as a multifactorial, progressive disease heavily influenced by metabolic, environmental, and occupational factors in Andhra Pradesh. Integrated strategies—combining primary prevention, early detection, and affordable treatment—are essential to curb the growing CKD burden in the region. Future research should explore geographical variations in etiology (e.g., fluoride toxicity) and cost-effective interventions for rural populations.

Conflicts of interests: None

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