Saudek C D, Hill Golden S
Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287-4904, USA.
Drugs Aging. 1999 May;14(5):375-85. doi: 10.2165/00002512-199914050-00005.
The use of insulin in elderly patients raises special considerations. Most people who develop diabetes mellitus late in life have type 2 diabetes mellitus, in which there is some residual endogenous insulin secretion. This pancreatic insulin secretion, when present, stabilises their metabolic status. However, some elderly people lose virtually all their endogenous insulin secretory capacity over time, or may even have type 1 (autoimmune) diabetes mellitus with no endogenous insulin. Generally, older patients with diabetes mellitus can be managed for years, often decades, with nutritional therapy and oral agents. More options exist now than did previously. In addition to a variety of sulfonylureas, there is metformin, troglitazone, and/or alpha-glucosidase inhibitors, that are viable options to be used before turning to insulin. The goals of insulin therapy in the elderly must be considered. When hyperglycaemia causes symptoms (polyuria, polydypsia and bodyweight loss) blood glucose levels are generally >200 mg/dl, and insulin is needed if maximal doses of oral agents have been used. Insulin is also indicated when hyperglycaemia puts patients at risk of hyperosmolar states, for example, when blood glucose is >300 mg/dl during a normal day. Clinical judgement dictates whether to use insulin to control glycaemia in the attempt to avoid long term complications such as neuropathy, retinopathy or nephropathy. In people with relatively short life expectancy, major comorbities and no sign of diabetic complications, the risk may be small. On the other hand, in patients for whom neuropathy, in particular, is a major risk, controlling glycaemia (with insulin if necessary) does reduce that risk. Most patients with type 2 diabetes mellitus can be managed with relatively simple insulin regimens thanks to their endogenous insulin secretion. A single bedtime dose of neutral protamine Hagedorn (NPH) insulin, with or without continuation of daytime oral agents, may control fasting blood glucose. A pre-mix combination of NPH and Regular insulin such as 70/30 or 50/50 may be used pre-meal. More customised, 'intensive' insulin regimens are needed when the glycaemia is unstable. Hypoglycaemia is clearly the most significant risk of insulin therapy. If mild and easily treated, it is of no real concern. On the other hand, nocturnal hypoglycaemia, and, in particular, hypoglycaemia unawareness, are clear signs that the insulin regimen should be modified. In summary, insulin therapy may be necessary, and can be used effectively, in elderly patients. However, risk:benefit considerations must be taken into account when deciding which patients to treat with insulin and what insulin regimen to use.
在老年患者中使用胰岛素需要特别考虑。大多数在晚年患糖尿病的人患有2型糖尿病，这类患者仍有一些内源性胰岛素分泌。这种胰腺胰岛素分泌若存在，可稳定其代谢状态。然而，一些老年人随着时间推移几乎丧失了所有内源性胰岛素分泌能力，甚至可能患有1型（自身免疫性）糖尿病且无内源性胰岛素。一般来说，老年糖尿病患者通过营养治疗和口服药物可控制病情数年，甚至数十年。现在的选择比以前更多。除了多种磺脲类药物外，还有二甲双胍、曲格列酮和/或α - 葡萄糖苷酶抑制剂，这些都是在使用胰岛素之前可行的选择。必须考虑老年患者胰岛素治疗的目标。当高血糖引起症状（多尿、多饮和体重减轻）时，血糖水平通常>200mg/dl，若已使用最大剂量口服药物仍需胰岛素治疗。当高血糖使患者处于高渗状态风险时，例如正常日血糖>300mg/dl时，也需要使用胰岛素。临床判断决定是否使用胰岛素控制血糖，以避免长期并发症，如神经病变、视网膜病变或肾病。对于预期寿命相对较短、有严重合并症且无糖尿病并发症迹象的患者，风险可能较小。另一方面，对于神经病变尤其是主要风险的患者，控制血糖（必要时使用胰岛素）确实可降低该风险。由于大多数2型糖尿病患者有内源性胰岛素分泌，他们可以采用相对简单的胰岛素治疗方案。睡前单次注射中性鱼精蛋白锌胰岛素（NPH），无论是否继续使用日间口服药物，都可控制空腹血糖。餐时可使用NPH与正规胰岛素的预混组合，如70/30或50/50。当血糖不稳定时，需要更个性化的“强化”胰岛素治疗方案。低血糖显然是胰岛素治疗最显著的风险。如果症状轻微且易于治疗，则无需真正担心。另一方面，夜间低血糖，尤其是低血糖无意识状态，是胰岛素治疗方案应调整的明显迹象。总之，胰岛素治疗在老年患者中可能是必要的，并且可以有效使用。然而，在决定哪些患者使用胰岛素治疗以及采用何种胰岛素治疗方案时，必须考虑风险与获益。
