Creatinine and diabetes

[Guest guest]

Docs:

Good article on creatinine levels as a predictor of risk for type 2

diabetes:

Lyndon McGill, D.C.

Salem, Oregon

March 13, 2009 — Lower serum levels of creatinine are associated with

increased risk of type 2 diabetes, according to a brief report in the

March issue of /Diabetes Care/.

The authors note that creatinine in serum is a direct indicator of total

muscle mass. " Although skeletal muscle is one of the major targets of

insulin, " write Dr. Tomoshige Hayashi, from Osaka City University

Graduate School of Medicine, Japan, and colleagues, " to our knowledge,

no prospective study has investigated the association between total

skeletal muscle mass and type 2 diabetes. "

The current investigation included 8570 men in the Kansai Healthcare

Study, an ongoing project examining risk factors for cardiometabolic

diseases. The participants were between 40 and 55 years of age and

nondiabetic at entry.

Incident diabetes was diagnosed if fasting glucose levels reached 126

mg/dL or higher or if treatment with an oral hypoglycemic agent or

insulin was initiated.

After 4 years of follow-up, 877 men were diagnosed with type 2 diabetes.

" The multiple-adjusted odds ratio for those who had serum creatinine

between 0.40 and 0.60 mg/dL was 1.91 compared with those who had levels

between 0.71 and 0.80 mg/dL, " the investigators report.

They conjecture that, because resistance training is known to cause

muscular hypertrophy, it might be worth exploring whether such training

could increase creatinine levels and thereby cut the risk of diabetes.

/Diabetes Care/. 2009;32:424-426.

Reuters Health Information 2009. © 2009 Reuters Ltd.

Clinical Context

No study has investigated the association between total skeletal muscle

mass and type 2 diabetes, although skeletal muscle is one of the major

target organs of insulin. Serum creatinine is a metabolite of creatine,

almost all of which is located in skeletal muscle. Because breakdown of

creatine is consistent and the amount of creatine per unit of skeletal

muscle mass is consistent, plasma creatinine concentration is stable and

reflects skeletal muscle mass.

This is a prospective observational study to examine the association

between serum creatinine levels and subsequent development of type 2

diabetes in Japanese men.

Study Highlights

* The cohort consisted of 11,063 Japanese men aged 40 to 55 years

without diabetes at baseline and with serum creatinine levels of

less than 2.0 mg/dL.

* Participants were all employees of 1 company and were not

malnourished.

* Diabetes was defined as a plasma fasting glucose level of 126

mg/dL or more or use of an antidiabetic medication or insulin.

* Follow-up was conducted annually for 4 years.

* 2493 men were lost to follow-up and were excluded from final analysis.

* Blood samples were drawn after a 12-hour fast for serum creatinine

levels.

* Questionnaires were administered to ask about physical activity,

smoking, alcohol consumption, and other lifestyle factors.

* The BMI was calculated based on weight and height.

* At baseline and at follow-up, type 2 diabetes was diagnosed if

fasting plasma glucose level was 126 mg/dL or higher or if the men

took hypoglycemic medication or insulin.

* Mean age at baseline was 48 years, mean BMI was 23 kg/m^2 , mean

fasting glucose level was 98 mg/dL, daily alcohol consumption was

27 g of ethanol, 41% to 73% were current smokers, and 12% had a

family history of diabetes.

* During 4 years of follow-up, type 2 diabetes developed in 877 men.

* The lowest category of creatinine levels (0.40 - 0.60 mg/dL) was

associated with type 2 diabetes in multiple adjusted models.

* After stratification by median BMI, the lowest category of

creatinine level was still significantly associated with type 2

diabetes.

* The authors concluded that low serum creatinine level was

associated with an increased risk for diabetes in Japanese men,

independent of BMI.

* They suggested that Asian men may have a lower percentage of total

skeletal muscle mass than Caucasians at the same BMI level, which

puts them at higher risk for diabetes.

* They also proposed increased resistance exercise to increase

muscle mass, which may reduce the risk for diabetes.

Pearls for Practice

* Serum creatinine level is a direct reflection of skeletal muscle mass.

* A lower serum creatinine level is associated with an increased

risk for the development of type 2 diabetes in Japanese men.