# Exercise as it relates to Disease/Physical activity and risk of end-stage kidney disease in the Singapore Chinese Health Study

This is a critique of the article “Physical activity and risk of end-stage kidney disease in the Singapore Chinese Health Study” created by u3090833.

## What is the background to this research?

In 2014-2015 203,400 Australian adults were living with diagnosed chronic kidney disease. The risk of chronic kidney disease increases with age and 3.6% of Australians aged 75 and over are suffering Australian Health Survey: Biomedical Results for Chronic Diseases, 2011-12. [Internet]. Canberra: Australian Bureau of Statistics; 2012. Chronic Kidney Disease Stages; 5/8/2013</ref>. In the over 60s those with signs of kidney disease are more likely to suffer physical or cognitive disability and are twice as likely to be admitted to hospital or require multiple GP visits Tanamas SK MD, Lynch B, Sethi P, Willenberg L, Polkinghorne KR, Chadban S, Dunstan D, Shaw JE. The Australian Diabetes, Obesity and Lifestyle Study Melbourne:Baker IDI Heart and Diabetes Institute;2012</ref>.
The most severe form of chronic kidney disease is end stage kidney disease AIHW. Cardiovascular disease, diabetes and chronic kidney disease -Australian facts: Prevalence and incidence Canberra:Australain Institute of Health and Welfare;2014 Report No: CDK 2.</ref>.In 2011-2012 1% of Australians were in end stage kidney disease. for which the only form of treatment is either kidney transplant or dialysis. Every year 101 in 1 million new cases of end stage kidney disease are reported. In 2012 there were 20,600 Australians receiving treatment for end stage kidney disease a number which had almost doubled since 2000.
The article chosen proposes that the risk of end stage kidney disease is lowered with regular physical activity in a dose dependent manner, the higher the intensity if the physical activity the lower the risk. While this study was not focused specifically on the Australian population the current high incidence rates of End Stage Kidney Disease in Australia make the findings worthy of further investigation.

## Where is the research from?

The data were collected as part of the Singapore Chinese Health Study with a large cohort of 59,552 Chinese adults aged 45–74 years. The participants were all residing in public housing in Singapore, originating from either the Fujian or Guangdong provinces of Southern China. Funding for this study was provided with grants from the U.S National Institutes of Health and the Singapore Ministry of Education, no funding was received from private organisations which helps to limit bias or investor influence.

## What kind of research was this?

The Singapore Chinese Health Study data was collected prospectively using an interview and person structured questionnaire which are reliable for assessing large cohorts due to their simplicity and cost effectiveness

## What did the research involve?

During the interviews participants we asked “on average, during the last year how many hours in a week did you spend in the following activities?”.
| Moderate Activities | Strenuous Activities |
| Walking briskly | Jogging |
| Cycling | Tennis |
| Tai chi | Aerobics. |
Accounts of moderate activity were given in intervals of:
* Never
* 30 min to <2 hours
* 2 to<4 hours
* 4 to<7 hours
* 7 to<10 hours
* 10 to <20 hours
* 20 to <30 hours
* 30 hours and above per week.
The methodology chosen was appropriate as questionnaires are useful in measuring physical activity levels in those with chronic kidney disease. However, this was also largest limitation to this study as self-reporting of physical activity through questionnaires comes with a high degree of over-reporting and there was no recorded physical assessment. Another important limitation is the lack of baseline kidney function measures and medications taken by the participants were not recorded nor was any impact that they may have had on their condition or health. Finally the ethnicity of the cohort is limited and may not be relevant for other populations.

## What were the basic results?

Of the 59,552 participants in the study 642 (1%) after the median 15.3 years follow up had developed end stage kidney disease. The rate of end stage kidney disease was higher (80 per 100,000) in those who did not partake in physical activity that those who did (60 per 100,000). There was a 24% lower risk for those who took part in regular physical activity and an independent 42% lower risk for those taking part in strenuous activity. The researchers have interpreted these results to be a clear association between increasing physical activity levels and a reduction in the risk of end stage kidney disease. However, these findings may be slightly over-emphasised considering the lack of data around medication use.

## What conclusions can we take from this research?

This study does show a potential to reduce the incidence of end stage kidney disease through increased physical activity levels however physical activity alone is not responsible for the onset.

## Practical advice

This research could be important when considering recommendations for those at risk of end stage kidney disease or for potential treatment. It may also be used for clinical public health guidelines and interventions for promotion of physical activity within the general population. Before taking on any new exercise regime it is important to discuss the implications with your doctor and to seek guidance from an accredited health professional such as an exercise physiologist. Any physical activity should not be a replacement for medication prescribed by your doctor but supplementary to it.

## Further information/resources

For further information visit :
* http://kidney.org.au/

## References

* 1 2
* 1 2
* 1 2
* ↑ Johansen KL, Painter P, Kent-Braun JA, Ng AV, Carey S, Da Silva M, et al. Validation of questionnaires to estimate physical activity and functioning in end-stage renal disease. Kidney International 2001;59(3):1121-7.
* ↑ Jafar TH, Jin A, Koh W-P, Yuan J-M, Chow KY. Physical activity and risk of end-stage kidney disease in the Singapore Chinese Health Study: Physical activity and kidney disease. Nephrology. 2015;20(2):61-7.
* 1 2 3 4
* ↑ Feene N, Waddington G, Chesworth W, Davey R, Cochrane T. Validating two self-reported physical activity measures in middle-aged adults completing a group exercise or home-based physical activity program. Journal of Science and Medicine in Sport, 2014; 17(6):611-616
* ↑ Yamagata K, Ishida K, Sairenchi T, Takahashi H, Ohba S, Shiigai T, et al. Risk factors for chronic kidney disease in a community-based population: a 10-year follow-up study. Kidney International. 2007;71(2):159-66.