Does hypokalaemia cause nephropathy? An observational study of renal function in patients with Bartter or Gitelman syndrome.

BACKGROUND: Hypokalaemic nephropathy has been described in patients with chronic potassium depletion; it is a condition in which proximal tubular vacuolization and interstitial fibrosis occur, resulting in a decline in glomerular filtration rate (GFR) and, in some cases, renal failure. It has been described in patients with chronic diarrhoea, eating disorders, laxative abuse and primary hyperaldosteronism; also occasionally in Bartter syndrome (BS), in which severe hypokalaemia accompanies significant renal sodium and water losses, though rarely in Gitelman syndrome (GS), in which there is equally severe hypokalaemia, but only modest sodium losses. AIM: We hypothesized that hypokalaemic nephropathy may not be due to potassium depletion per se, but persistently elevated circulating levels of aldosterone, possibly with superimposed episodes of renal hypoperfusion. DESIGN AND METHODS: We searched UK and European data sets to retrospectively compare serum and urinary parameters in patients with GS and BS. RESULTS: The patients with GS often had lower serum potassium concentrations than patients with BS, but the BS patients had significantly higher serum creatinine concentrations and lower estimated GFRs (eGFR). BS patients had significantly higher fractional excretions of sodium compared with GS patients, as well as higher plasma renin activities and serum aldosterone levels. CONCLUSION: These findings show that in genetically confirmed cases of BS and GS, the degree of hypokalaemia (as an index of chronic potassium depletion) does not correlate with GFR, and that on-going sodium and water losses, and consequent secondary hyperaldosteronism, may play a more important role in the aetiology of hypokalaemic nephropathy.

First-time hospital admissions with illicit drug problems in indigenous and non-indigenous Western Australians: an application of record linkage to public health surveillance.

OBJECTIVE: To monitor incidence rates of first-time hospital admission with an illicit drug problem in the Indigenous and non-Indigenous populations of Western Australia in 1980-95. METHOD: Some 10,533 first admissions among 16,294 total admissions mentioning any of 19 groups of illicit drug problems were identified using linked hospital separation data from the WA Health Services Research Linked Database. RESULTS: Trends in age-standardised rates showed two distinct features: a rapid acceleration in first-time admission rates commencing from about 1991; and a cross-over of the rates in Indigenous and non-Indigenous people. In 1980, the rates were 9.2 per 100,000 PY in Indigenous and 16.4 per 100,000 PY in non-Indigenous people. By 1995, the respective rates were 180.7 and 95.5 per 100,000 PY. Largest proportional increases were observed in first-time admissions mentioning amphetamine dependence or abuse, although increases were seen also in problems due to opiates, hallucinogens, cocaine and cannabis. CONCLUSION: The results are consistent with data on the rising use of injectable amphetamines and other illicit drugs, especially among Aboriginal people. IMPLICATIONS: Urgent attention is required to identify ways of reducing health problems due to illicit substance use in both Indigenous and non-Indigenous Australians.

Trends and patterns of drug-caused mortality in Australia and Western Australia.

OBJECTIVE: To estimate the number of drug-caused deaths and compare patterns and trends of drug-caused mortality in Western Australia (WA) and Australia. METHOD: Aetiologic fractions were applied to mortality data for WA (1985-96) and Australia (1991-96) to estimate the number of deaths due to alcohol, tobacco and other drugs. RESULTS: Age-standardised rates (ASR) for smoking and alcohol-caused deaths fell significantly, while the ASR for deaths caused by other drugs increased significantly. About 85% of drug-caused deaths occurred among people aged 50 years and above. Tobacco-caused deaths mainly occurred among the elderly. Alcohol-caused death rates showed a minor peak in those aged 20-24 years then, from middle age, began to rise steadily, peaking in the oldest age group. However, deaths due to other drugs occurred mainly among young people, particularly those aged 25-34 years. These age differences were reflected in the person years of life lost (PYLL). People who died from other drugs lost, on average, about 31 years of life, twice as many as people who died from alcohol-caused conditions and about six times the average number of PYLL per tobacco-caused death. CONCLUSIONS: Nearly a fifth of all deaths were due to drugs and 80% of drug-caused deaths were due to tobacco smoking. The patterns and trends of drug-caused mortality in WA were similar to those Australia wide. IMPLICATIONS: Strategies highlighting the negative impact of tobacco and alcohol on health need to be maintained as well as programs which target illicit drug use.

Estimating the cost of hospital treatment for injuries using linked morbidity data.

This paper describes the analysis of injury-related linked hospital morbidity data by admissions and by individual patients in Western Australia (WA) from 1990 to 1994. Over this five-year period, there were an average of 35,385 admissions and 30,524 people admitted each year for injuries in WA. The age-standardised rates for injury-related hospital admissions and persons admitted for injuries increased significantly, by 2.4% and 1.5% per year respectively, over the five-year period. The number of admissions and the number of persons admitted peaked in the 20-24 years age group but the highest rates were among those aged 75 years and above. Injuries accounted for nearly 10% of all hospital bed day costs and cost about $50 per head of population per year. The cost of hospitalisation rose steadily from $85.2 million in 1990 to $113.6 million in 1994, the average cost being nearly $100 million per year. The average cost per injury related hospital episode was $2,748. Generally, the cost per hospital episode was higher for males and increased with age, following a similar pattern to that for the average length of stay.

The WA Hospital Morbidity Data System: an evaluation of its performance and the impact of electronic data transfer.

The paper evaluates the performance of the Hospital Morbidity Data System, maintained by the Health Statistics Branch (HSB) of the Health Department of Western Australia (WA). The time taken to process discharge summaries was compared in the first and second halves of 1995, using the number of weeks taken to process 90% of all discharges and the percentage of records processed within four weeks as indicators of throughput. Both the hospitals and the HSB showed improvements in timeliness during the second half of the year. The paper also examines the impact of a recently introduced electronic data transfer system for WA country public hospitals on the timeliness of morbidity data. The processing time of country hospital records by the HSB was reduced to a similar time as for metropolitan hospitals, but the processing time in the hospitals increased, resulting in little improvement in total processing time.