Smoking (also in habitual smokers) acutely impairs insulin action and leads to insulin resistance. Thus, smoking can be of importance for the development of the insulin resistance syndrome associated with risk for cardiovascular disease.

Diabetes occurs frequently in patients with pancreatic cancer. To investigate the impact to tumour removal, seven patients were studied before and after 85 per cent subtotal pancreatectomy for adenocarcinoma of the pancreas. The frequency of diabetes was determined by the oral glucose tolerance test. Fasting levels of C peptide and insulin were measured in plasma, and insulin secretion was investigated by hyperglycaemic glucose clamp and glucagon stimulation. Six of the seven patients were diabetic before surgery and four required insulin treatment. Improvements in diabetic status and glucose metabolism were found in all seven patients after operation, as demonstrated by increased glucose metabolic capacity during hyperglycaemia. This occurred despite a postoperative reduction in insulin secretion and is explained by the observed augmentation of whole-body insulin sensitivity after surgery. A diabetogenic factor may be produced by pancreatic adenocarcinoma that may be responsible, directly or indirectly, for the high frequency of diabetes in patients with pancreatic cancer.

No abstract

Hemoglobinometry according to the International Committee of Standardization in Hematology (ICSH) suffers from imprecision related to high sample dilution and from potential errors owing to sample turbidity. We have evaluated a new instrument, "HemoCue," that measures hemoglobin at two wavelengths as azide methemoglobin, without dilution. The HemoCue method is superior to the ICSH method: by correction for turbidity, it avoids false hemoglobin readings that may arise from hyperlipemia or some large M-component of the immunoglobulin M class. We find the equipment suitable for use in outpatient units.

Recent studies have indicated that serum and plasma cystatin C are better markers for glomerular filtration rate (GFR) than serum creatinine, ubiquitously used for this purpose. To fully exploit the value of serum and plasma cystatin C as GFR markers, reliable age and sex-correlated reference intervals are required. The present study comprised cystatin C determinations in plasma and sera from 259 individuals from a well-defined area in the southernmost part of Sweden. From demographic lists two men and two women were randomly selected from each one-year birth cohort above 20 years of age. No sex differences were found for plasma and serum cystatin C, whereas an increase in the cystatin C levels with age was noted, corresponding to the known age-related decrease in GFR. The following reference intervals are recommended for practical clinical use: S-Cystatin C (both sexes): 20-50 years, 0.70-1.21 mg l-1 and 50+ years, 0.84-1.55 mg l-1. The same samples were also used for determination of beta 2-microglobulin levels in order to calculate reference intervals for the beta 2-microglobulin/cystatin C-ratio, which is a more distinct marker for cell proliferation, particularly lymphoproliferation, than is the serum level of beta 2-microglobulin alone, since the ratio should be virtually uninfluenced by GFR. The beta 2-microglobulin/cystatin C-ratios were uninfluenced by sex and age and 1.45-2.43 is recommended as the serum reference interval for practical clinical use. Serum creatinine was determined in the same samples and the creatinine level was found to be strongly influenced by sex and weakly by age.