Older patients with type 2 diabetes are at higher risk of chronic kidney disease (CKD) if they had reduced intrinsic capacity, suggests a study from Taiwan recently published as a preprint on Research Square.¹ The presence of obesity, sarcopenic obesity in particular, further enhanced this risk.

A total of 2482 patients, mean age 72 years, who had been diagnosed with type 2 diabetes between 2006 and 2021 were enrolled in this cross-sectional study to examine the impact of intrinsic capacity and obesity on risk of CKD. None of the selected subjects had any evidence of a nondiabetic kidney disease (such as polycystic kidney, primary glomerular diseases) and were otherwise healthy. The WHO Integrated Care for Older People (ICOPE) screening tool was used to evaluate the intrinsic capacity of each participant including assessment for cognitive decline, limited mobility, malnutrition, visual impairment, hearing loss and depressive symptoms. Obesity was graded on the basis of BMI with normal weight ranging from 18.5 to < 24 kg/m2, overweight 24 to < 27, mild obesity as BMI 27 to <30, moderate obesity 30 to < 35 and severe obesity >35 kg/m2.  Estimated glomerular filtration rate (eGFR), urine albumin-to-creatinine ratio (UACR) and the 2012 KDIGO criteria  were used to risk stratify CKD as low, moderately increased, high and very high.

The average duration of type 2 diabetes among the participants was 14 years. The mean eGFR was 69 mL/min/1.73 m2 and the median UACR was 19 mg/g. The intrinsic capacity score was 0 in the majority of patients (61.4%). In 26.4%, the score was 1. In 12% patients, the score ranged from 2 to 5.

Compared to patients with an intrinsic capacity score of 0 or 1, those with scores of  2 to 5 had long-standing diabetes. They tended to be female, older, and have higher BMI (severe obesity). They were also more likely to use OHAs/insulin. The risk of CKD increased with increase in the intrinsic capacity score. The risk (moderate to very high) was 76% higher in patients with score 2-5 compared to those with score of 0 with odds ratio of 2.57).  Even those with a score of 1 were at risk of CKD with OR of 1.36.

Obesity and the intrinsic capacity score also had a synergistic impact on CKD risk, which increased nearly three times among those with score of 1-5 and moderate/severe obesity (OR 2.71) versus nonobese participants with a score of 0.

Intrinsic capacity is a new concept introduced by the WHO for healthy aging. This is the Decade of Healthy Ageing (2021-2030). Healthy aging “the process of developing and maintaining the functional ability that enables wellbeing in older age”. The interaction of intrinsic capacity and the environment is functional ability. Intrinsic capacity, as per WHO is “the combination of the individual’s physical and mental, including psychological, capacities”.² Both intrinsic capacity and functional ability decline with advancing age. Any underlying disease also adversely impacts the intrinsic capacity and functional ability.

This study is the first to use intrinsic capacity to gauge the risk of CKD in older diabetic patients, note the authors. It showed that the older type 2 diabetes patients with higher intrinsic capacity scores were at higher risk of developing CKD.

Assessment of impaired intrinsic capacity and obesity can help identify older type 2 diabetes patients at risk of CKD much before any deviations in the conventional markers of renal function (UACR, eGFR and serum creatinine) become evident. Early intervention in these patients can prevent the onset of CKD.

References

1. Wei-Hua Tang, et al. Interactive effects of intrinsic capacity and obesity on the risk of chronic kidney disease in older patients with type 2 diabetes mellitus. Research Square. July 14, 2022 DOI: https://doi.org/10.21203/rs.3.rs-1825516/v1.
2. Integrated care for older people (ICOPE): Guidance for person-centred assessment and pathways in primary care. Geneva: World Health Organization; 2019 (WHO/FWC/ALC/19.1).