C. M. Lofthus

Epidemiology of hip fractures in Oslo, Norway

The incidence of hip fractures in Oslo has shown a secular increase during the past decades. The main aims of the present study were to report the current incidence of hip fractures in Oslo and to determine whether there is a seasonal variation in the occurrence of fractures. Using the electronic diagnosis registers and the lists of the operating theater for the hospitals in Oslo with somatic care, all patients with ICD-9 code 820.X (hip fracture) from May 1, 1996 to April 30, 1997 were identified. Medical records for all identified patients were obtained and diagnosis was verified. Using the population of Oslo on January 1, 1997 as the population at risk, the age- and gender-specific annual incidence rates were calculated. These rates were compared with those for 1988/89 and 1978/79. Outdoor temperature data for Oslo were obtained to study the relation between temperature and number of hip fractures. A total number of 1316 hip fractures was included, of which 78% occurred in women. An exponential increase in incidence with age was observed in both genders. The age-adjusted fracture rates per 10,000 for the age group > or =50 years were 118.0 and 44.0 in 1996/97, 124.3 and 44.9 in 1988/89, and 104.5 and 35.8 in 1978/79 for women and men, respectively. There was no significant seasonal variation in the incidence of hip fractures and no correlation between mean outdoor temperature and number of fractures for each month in 1996/97. The data show that the incidence of hip fractures in Oslo has not changed significantly during the last decade, and it is still the highest reported. The cold climate of Oslo does not seem to contribute to the high incidence.

More postoperative femoral fractures with the Gamma nail than the sliding screw plate in the treatment of trochanteric fractures

Despite several studies showing a higher incidence of peri-implant femoral fractures with the Gamma nail than with a sliding screw plate (SSP), the Gamma nail has remained the standard implant for trochanteric fractures in many hospitals. We recorded 921 trochanteric fractures in the city of Oslo during 2 years and compared the reoperation frequency in patients treated with the Gamma nail (n 379) and SSP (n 542). The distribution of age and gender in the two treatment groups was the same. 65 patients were reoperated on, several of them more than once. The only significant difference between the two surgical methods in complications leading to a reoperation was the frequency of femoral shaft fractures. 17 of the patients treated with the Gamma nail had a new femoral fracture postoperatively, compared to 3 of those with a SSP. The relative risk of another femoral fracture after surgery was 12 (95% CI: 2.7-52) if the surgical device was a Gamma nail compared to a SSP.The Gamma nail therefore can not be recommended as the standard implant for trochanteric fractures.

Vitamin D status in Sri Lankans living in Sri Lanka and Norway

Vitamin D deficiency is common in non-Western immigrant groups living in Western countries. A comparison of vitamin D status in individuals who have emigrated and individuals who remain in their country of origin is needed in order to provide information about the effect of moving to northern latitudes. A total of 196 participants aged 30-60 years in a cross-sectional population-based study in Kandy, Sri Lanka (latitude 7 degrees north) and 242 Sri Lankans aged 31-60 years participating in a cross-sectional population-based study in Oslo, Norway (latitude 60 degrees north) were included in the analysis. All serum samples were analysed for serum 25-hydroxyvitamin D (s-25(OH)D) in the same laboratory. Sri Lankans living in Norway had substantially lower s-25(OH)D (mean 31.5 nmol/l) compared with those living in Sri Lanka (mean 54.2 nmol/l), and the prevalence of s-25(OH)D < 25 nmol/l was 9.3 times higher (95 % CI 4.4, 19.6) in Norway compared with Sri Lanka. In Sri Lanka there was a clear seasonal variation with the lowest s-25(OH)D levels in August-September and the highest levels in November-December. We conclude that vitamin D status among Sri Lankans living in Kandy, Sri Lanka was considerably higher than that among Sri Lankans living in Oslo, Norway. The low vitamin D status commonly observed in non-Western immigrant groups living at northern latitudes should not be regarded as normal levels for these groups. However, also in Sri Lanka we found a profound seasonal variation with the lowest levels in August and September after the Monsoon.

A randomised comparison of increase in serum 25-hydroxyvitamin D concentration after 4 weeks of daily oral intake of 10 μg cholecalciferol from multivitamin tablets or fish oil capsules in healthy young adults

Many types of vitamin supplements are available on the market, but little is known about whether cholecalciferol obtained from fat-containing capsules differs in bioavailability from that of solid tablets. Our objective was to test whether 4 weeks of daily supplementation with 10 mug cholecalciferol given as a fish oil capsule produces a larger increase in serum 25-hydroxyvitamin D (s-25(OH)D) concentration compared with the same dose of cholecalciferol given as a multivitamin tablet. A total of seventy-four healthy subjects aged 19-49 years were initially included and fifty-five of these completed the study and fulfilled the inclusion criteria. After completing a self-administered questionnaire about diet and sunshine exposure and having a non-fasting venous blood sample drawn, participants were randomised to receive daily multivitamin tablets (n 28) or fish oil capsules (n 27), each containing equal doses of cholecalciferol. A second blood sample was drawn after 28 d. Mean baseline s-25(OH)D was 40.3 (sd 22.0) nmol/l in the multivitamin group and 48.5 (24.8) nmol/l in the fish oil group. When controlling for baseline s-25(OH)D, mean 4-week increase in s-25(OH)D was 35.8 (95 % CI 30.9, 40.8) nmol/l in the multivitamin group and 32.3 (95 % CI 27.3, 37.4) nmol/l in the fish oil group; the mean difference was 3.5 (95 % CI - 3.6, 10.6) nmol/l (P = 0.33). The results were unaltered by statistical adjustment for BMI, ethnic background, age and sex. We conclude that fish oil capsules and multivitamin tablets containing 10 microg cholecalciferol administered over a 4-week period produced a similar mean increase in s-25(OH)D concentration.

The treatment of femoral neck fractures

BACKGROUND About 5000 people fracture their femoral neck every year in Norway. Mean age is about 83 years and about 3/4 are women. For more than 50 years the alternatives have been internal fixation or arthroplasty. In Norway, the tradition has been internal fixation. Recent studies, however, support the use of arthroplasty. The article provides a review on the treatment of femoral neck fractures. MATERIAL AND METHODS The article is based on literature identified through a non-systematic search in Medline. RESULTS Internal fixation has a higher risk of treatment failure (30 - 40 % in displaced fractures) than arthroplasty (less than 10 %). In elderly patients with displaced fractures, arthroplasty provides better hip function than internal fixation. Most patients should be treated with hemiarthroplasty, but total hip arthroplasty may give better function in the healthiest and fittest of the elderly patients. In patients younger than 60 - 65 years, internal fixation should be attempted, even though the failure rate is about 30 %. Undisplaced fractures should be treated with internal fixation, irrespective of age. The risk of treatment failure is about 10 %. INTERPRETATION Elderly patients with displaced femoral neck fractures should be treated with arthroplasty, usually hemiarthroplasty. Osteosynthesis should normally be reserved for undisplaced fractures and fractures in young and otherwise healthy patients.

Changes in the vitamin D endocrine system and bone turnover after oral vitamin D3 supplementation in healthy adults: results of a randomised trial

BackgroundThere is uncertainty as to which intake of vitamin D is needed to suppress PTH and maintain normal bone metabolism throughout winter at northern latitudes. We aimed to investigate whether four weeks’ daily supplementation with 10 μg vitamin D3 from fish oil produced a greater change in serum vitamin D metabolites, parathyroid hormone, and bone turnover in healthy adults compared with solid multivitamin tablets. Furthermore, it was studied whether age, gender, ethnic background, body mass index, or serum concentrations at baseline predicted the magnitude of change in these parameters.MethodsHealthy adults aged 19–48 years living in Oslo, Norway (59°N) were randomised to receive a daily dose of 10 μg vitamin D3 given as fish oil capsules or multivitamin tablets during four weeks in late winter. Serum samples from baseline and after 28 days were analysed for 25-hydroxyvitamin D (s-25(OH)D), 1,25-dihydroxyvitamin D (s-1,25(OH)2D), intact parathyroid hormone (s-iPTH), and osteoclast-specific tartrate-resistant acid phosphatase 5b (s-TRACP). Fifty-five eligible participants completed the intervention (74% of those randomised).ResultsS-25(OH)D increased by mean 34.1 (SD 13.1) nmol/l, p < 0.001; s-iPTH decreased by mean 1.2 (SD 2.5) pmol/l, p = 0.001; s-1,25(OH)2D increased by mean 13 (SD 48) pmol/l, p = 0.057; and s-TRACP increased by mean 0.38 (SD 0.33) U/l, p < 0.001. For all these parameters, there was no difference between fish oil and multivitamin formulation. Baseline concentrations were the only independent predictors of changes in biochemical parameters.ConclusionsFour weeks of daily supplementation with 10 μg vitamin D3 decreased mean s-iPTH and increased s-TRACP concentration, and this did not differ by mode of administration. Our results suggest an increased bone resorption following vitamin D supplementation in young individuals, despite a decrease in parathyroid hormone levels.Trial RegistrationClinicalTrials.gov: NCT01482689

Procollagen type 1 amino-terminal propeptide (P1NP) and risk of hip fractures in elderly Norwegian men and women. A NOREPOS study

The current study aimed to assess a possible association between the bone turnover marker procollagen type 1 amino-terminal propeptide (P1NP) and future hip fractures in elderly Norwegian men and women and to elucidate the relation between P1NP, bone mineral density and 25-hydroxyvitamin D (25(OH)D). Men and women aged 71 to 77 from two population based health studies in Norway (1999-2001) were followed for a median period of 7.3 years with respect to hip fractures. The study was designed as a case-cohort study. P1NP and 25(OH)D were analysed in frozen serum samples obtained at baseline in hip fracture patients (n=340) and in randomly selected sex stratified sub-cohorts. Bone mineral density was measured by dual-energy X-ray absorptiometry (DXA) in a subset of participants. Cox proportional hazards regression with inverse probability weighting and robust variance was performed. No significant correlation between 25(OH)D and P1NP was found. A negative correlation between P1NP and BMD was observed in women (Rho=-0.36, p=0.001). A similar trend was observed in men. No association between quartiles of P1NP and rate of subsequent hip fractures was found. Spline analyses suggested a higher rate of hip fracture at P1NP levels above 60 μg/L in both men and women. A higher hip fracture rate, which was independent of BMD, was also indicated in women with very low levels of P1NP.

Database Validity in Assessing Population Trends in Hip Fracture Rates in Canada

a decrease in AMI hospital volume because of the approach we took to estimation. The method we used to estimate RSMR is via hierarchical modeling, which will shrink “outlying” observations. While the amount of shrinkage does relate to the AMI hospital volume, it also relates to case-mix, overall mean performance, deviations from mean performance, and the relative AMI volumes of other hospitals. Only under very strict circumstances (eg, the relative reduction of all the hospital AMI volumes would need to be the same for all hospitals, the outliers would need to be the same from year to year, and the performance of each hospital would need to be the same from year to year) could the reduction in between-hospital variation in RSMRs be attributable only to a reduction in hospital volume. Moreover, the national average mortality following AMI decreased. The second hypothesis raised by Blumberg posits that the reduction is attributable to error in reporting of risk factors, because this will bias the denominator of an RSMR. If there were systematic errors in estimating the total number of expected AMI mortalities at specific hospital types attributable to upcoding or downcoding specific comorbid conditions, this could confound estimates of expected mortality rates for classes of hospitals. We have confirmed that the strength of the association between the covariates and the outcomes remained relatively constant over the period evaluated in the article. For that reason, we believe that it is unlikely that the change we observed was a result of upcoding of the covariates.