Medications> Complementary and Alternative Medicines>

DEFINITION

• Non-herbal compounds are used by patients for the complementary and/or alternative treatment of DM.
• Few have been systematically evaluated for efficacy and safety
• Non-herbal compounds which have had controlled evaluation are discussed in this module.

CLINICAL TREATMENT

• Essential trace element with an important role in carbohydrate and lipid metabolism. Chromium deficiency leads to reversible insulin resistance and diabetes.
• Most common forms are chromium picolinate and Brewer's yeast
• Doses of 200 to 1000 µg for 6 to 26 weeks reduced HbA_1c levels by an average of 0.6% (95% CI -0.9% to -0.2%) and FBG levels by an average of 1 mmol/L (95% CI-1.4 to -0.5) in a recent meta-analysis. More than half of the studies examined were deemed poor quality. (Pittler)
• May have modest effect on weight in randomized trials (1.1 kg reduction over 6-14 weeks) (Pittler) and may attenuate sulfonylurea-related weight gain (Martin)
• No significant adverse effects were reported in any of the reviewed trials.
• There are no known interactions with other medications.
• Although initial clinical trials appear promising, larger, well-designed clinical studies are needed before chromium can be recommended.

• Trace element which may inhibit phosphotyrosine phosphatase enzymes that affect the insulin receptor (Verma)
• Vanadyl sulfate or sodium metavanadate 50 to 300 mg/d given over 3-6 weeks have shown reductions in fasting blood glucose of 13-40 mg/dL and HgbA1c of 0.4-0.8% in small, uncontrolled trials (Smith). One recent study (Jacques-Camerena), showed no benefit on insulin sensitivity, but increases in triglycerides.
• Side effects were common including gastrointestinal upset, bloating, and nausea.
• Vanadium cannot be recommended for the treatment of diabetes.

• Observational studies demonstrate an association between type 2 diabetes and vitamin D deficiency.
• Possible mechanisms supporting causal association include a role of vitamin D in beta-cell function, insulin action, reduction of systemic inflammation. Calcium may also affect insulin action and secretion.
• Clinical trials have no demonstrated clear benefit of either calcium or vitamin D supplementation for the treatment of hyperglycemia. One post hoc analysis of a randomized clinical trial showed that daily doses of D3 700 IU and Calcium 500 mg attenuated the rise in glycemia and insulin resistance over 3 years in patients with baseline impaired glucose tolerance (Pittas).
• Further studies are needed to confirm a benefit of vitamin D and calcium in the management of diabetes and determine the optimal dosing. Because osteoporosis and fractures are common in patients with diabetes, daily doses of 1000-1200 mg of calcium and 800-1000 IU of Vitamin D should be recommended for bone health.

EXPERT COMMENTS

• Chromium may show some benefit for improving glucose metabolism in patients with diabetes. Larger studies of longer duration are needed before chromium can be recommended for routine use.

REFERENCES