What is Diabetes Mellitus?
Diabetes mellitus results from lack, or reduced effectiveness, of endogenous insulin. Hyperglycemia is one aspect of a far-reaching metabolic derangement. Which causes serious microvascular (retinopathy, nephropathy, neuropathy) or macrovascular problems: stroke, MI, renovascular disease, limb ischemia. So think of Diabetes mellitus as a vascular disease: 1 adopt a holistic approach and consider other cardiovascular risk factors too.
Causes of Diabetes Mellitus:
Steroids; anti-HIV drugs; newer antipsychotics.
• Pancreatic: pancreatitis; surgery (where >90% pancreas is removed); trauma. Pancreatic destruction (haemochromatosis, cystic fibrosis); pancreatic cancer.
• Cushing’s disease; acromegaly; pheochromocytoma; hyperthyroidism; pregnancy.
• Others: congenital lipodystrophy; glycogen storage diseases.
What is the best diet for obese patients with type 2 diabetes?
Dietary carbohydrate is a big determinant of postprandial glucose levels. Low-carbohydrate diets improve glycemic control. How do low-carbohydrate, ketogenic diets (<20g of carbohydrate daily; LCKD) compare with low-glycemic index, reduced-calorie diet (eg 500kcal/day deficit from weight maintenance diet)? In one randomized study over 24 weeks, LCKD had greater improvements in HbA1c (Ω15 vs Ω5mmol/L), weight (Ω11kg vs Ω7kg), and HDL. Diabetes drugs were reduced or eliminated in 95% of LCKD vs 62% of LGID participants.
Treating diabetes mellitus:
General: Focus on education and lifestyle advice (eg exercise to ⇡insulin sensitivity), healthy eating: ↓saturated fats, ↓sugar, ↑starch-carbohydrate, moderate protein. Foods made just for diabetics are not needed. One could regard bariatric surgery as a cure for Diabetes mellitus in selected patients. Be prepared to negotiate HbA1c target and review every 3–6 months. Assess global vascular risk; start a high-intensity statin , eg atorvastatin as tolerated, control BP. Give foot-care. pregnancy care should be in a multidisciplinary clinic. Advise informing DVLA and not to drive if hypoglycemic spells; loss of hypoglycemia awareness may lead to loss of license; permanent if HGV).
Oral hypoglycemic agents:
Metformin: A biguanide. ↑ insulin sensitivity and helps weight. SE: nausea; diarrhea. (try modified-release version); abdominal pain; not hypoglycemia. Avoid if eGFR ⥶36mL/min (due to risk lactic acidosis). DPP4 inhibitors/gliptins: (Eg sitagliptin.) Block the action of DPP-4, an enzyme which destroys the hormone incretin. Glitazone: ↑ insulin sensitivity; SE: hypo glycaemia, fractures, fluid retention,↑ LFT (do LFT every 8wks for 1yr, stop if ALT up >3-fold). Sulfonylurea: Blocks the reabsorption of glucose in the kidneys and promotes excretion of excess glucose in the urine (eg empagliflozin, shown to reduce mortality from cardiovascular disease in patients with type 2 DM, when compared to placebo).
Vital to educate to self-adjust doses in the light of exercise, finger prick glucose, calorie intake, and carbohydrate counting.
•Phone support (trained nurse 7/24).
•Partner can abort hypoglycemia: sugary drinks; Gluco Gel® PO if coma (no risk of aspiration). It is vital to write UNITS in full, when prescribing insulin to avoid misinterpretation of U for zero.