SYMPTOMS OF HEAT STRESS PREDICT SERUM CREATININE RISES IN PATIENTS WITH CHRONIC KIDNEY DISEASE DURING HEAT WAVE CONDITIONS IN UTTAR PRADESH, INDIA

7 Feb 2025 12 a.m. 12 a.m.
WCN25-AB-1360, Poster Board= FRI-509

Introduction:

Heat waves are defined as temperatures of 40ºC in the plains, with temperature departure greater than 4-6ºC from the usual in at least two recording stations in the region, and such heat waves being recorded across several stations across central and eastern Uttar Pradesh in the month of May 2023 and 2024, during which period, the present study was conducted. We hypothesized that transient serum creatinine increases occur among patients with chronic kidney disease (CKD) conforming to the CKD of unknown etiology (CKDu) phenotype, during heat wave conditions. The aim of the study was to therefore assess serum creatinine (SCr) changes during and a month after a heat wave (HW) (ΔPost-Pre HW SCr), and study its predictors.

Methods:

The study participants were recruited in the months of April-May of years 2023 and 2024, from an ongoing hospital-based registry for patients with unexplained chronic kidney disease from central and eastern districts of Uttar Pradesh, fulfilling criteria for CKDu as per Indian Society of Nephrology CKDu consensus criteria. In addition to clinical, socioeconomic, occupational information, outdoor work hours, and symptoms of heat stress [modified from health hazard evaluation of heat stress (HETA questionnaire)] were noted. Renal function tests at study inclusion and at the next visit advised at one month were noted, among study participants. All those reporting any heat stress symptoms were advised for maintaining hydration, avoiding continuous outdoor heat exposure > 2 hours and continued on the usual care for CKD management.

Results:

A total of 266 study participants were screened for participation and 138 were included in the final analysis (who had completed the HETA questionnaire and had paired serum creatinine values measurements one month apart from the Biochemistry lab in the study institution providing isotope dilution mass spectrometry (IDMS)-traceable values. Table 1 shows the baseline clinical, socioeconomic and occupational characteristics of the enrolled participants, belonging to agricultural and non-agricultural background. A total of 81 study participants showed recovering serum creatinine after heat wave – a negative ΔPost-Pre HW SCr and 57 showed static or worsening values. Figure 1 shows the significantly higher mean heat stress index in the group with negative  ΔPost-Pre HW SCr. Table 2 shows the predictors of ΔPost-Pre HW SCr using univariate and multivariate logistic regression analysis. It can be seen that from a model containing estimated glomerular filtration rate (eGFR), being an agricultural worker, history of use of alternative medications and the heat-stress index, only heat stress index and a eGFR were the two significant predictors of heat wave induced serum creatinine rise.

Table 1: Comparison of clinical and occupational characteristics among agricultural and non-agricultural study participants:

 

Occupation: agriculture

(n=57)

Occupation: others

(n=80)

p-value

Age (years)

51 (42-62)

43 (32-57)

0.678

Males: females

37:20

36:44

0.02

CKD stage II

                   III

                   IV

                   V

2

26

16

14

1

27

22

30

 

Hypertension requiring less than 2 antihypertensives

65.5%

63.7%

0.859

Remote agricultural work (>5 years ago)

NA

4.9%                

 

Non-farm occupations:

Household work, animal husbandry, transportation, shopkeeping

Household work, industrial and household manufacturing, services, repairing, construction work, transportation, shopkeeping

 

Duration of agricultural work

< 3 months: 26.2%

3-6 months: 18.9%

6-12 months: 54.9%

NA

 

Study participants with outdoor work > 3 hours/day (%)*

70%

45%

0.03

Duration of outdoor work*

6 months (5-11)

4 months (2-7)

0.02

Pesticides kept at home

32.0%

5.6%

0.56

Spraying of pesticides

With precautions and protective equipment

 

Without precautions and protective equipment

 

18%

 

 

50%

 

 

 

 

2.8% (remote use)

 

Source of drinking water

Groundwater

Rivers

Ponds, lakes

 

99.2%

 

0.8%

 

 

98.6%

0.7%

0.7%

 

Painkiller use in the past six months

29.5%

28.9%

0.595

Alternative medicine use

20.7%

21.5%

0.15

Table 2: Table 2: Predictors of heat wave induced serum creatinine rise (ΔPost-Pre HW SCr):

 

Exp (B)

95% CI of Exp (B)

p-value

Univariate

      

Age

1.005

0.982-1.027

0.693

Estimated glomerular filtration rate

0.980

0.958-1.003

0.082

Agriculture as occupation

1.857

0.920-3.748

0.084

Use of alternative medications

3.111

1.005-9.630

0.049

Heat stress index

1.176

1.061-1.304

0.002

Multivariate

      

Estimated glomerular filtration rate

1.028

1.003-1.053

0.028

Heat stress index

1.196

1.076-1.329

0.001

Conclusions:

Heat wave conditions are associated with reversible renal dysfunction in patients with CKD, and such dysfunction may be predicted by lower eGFR and higher heat stress index elicited on the modified HETA questionnaire. These identified characteristics may be used to identify individuals with CKD at a high risk of heat-stress injury, and can be targeted for prevention of such injury.

I have no potential conflict of interest to disclose.

I did not use generative AI and AI-assisted technologies in the writing process.