Klift, M. van de

Cushing's syndrome due to ectopic ACTH production by (neuroendocrine) prostate carcinoma (Article)

2009-01-01T00:00:00Z

Ectopic adrenocorticotropin (ACTH) secretion accounts for less than 10% of all causes of endogenous Cushing's syndrome (CS) and is usually associated with neuroendocrine tumors and small cell carcinoma of the lung. We report the case of a 62-year-old man with CS due to ectopic ACTH production by small cell carcinoma of the prostate. He presented with severe hypercortisolism and associated symptoms. Plasma neuron specific enolase (NSE) was grossly elevated. Despite performing a laparoscopic bilateral adrenalectomy, the patient died as a result of sepsis with multi-organ failure. Post-mortem immunohistochemical staining of prostate tumor tissue showed ACTH expression. ACTH staining was also performed in four additional patients with small cell carcinoma of the urinary tract without CS. None of these additional cases showed a positive staining for ACTH. Although a rare cause of ectopic ACTH production, neuroendocrine prostate carcinoma should be considered in male patients with Cushing's syndrome, in particular in those with an occult source of ACTH overproduction.

Endogenous sex hormones, sex hormone-binding globulin, and the risk of incident vertebral fractures in elderly men and women: the Rotterdam Study. (Article)

2004-07-01T00:00:00Z

In an age-matched, case-control study, we investigated the association between endogenous sex steroid hormones and incident vertebral fractures in both elderly men and women (aged 67.7 +/- 6.8 yr). Drawn from the Rotterdam Study, participants required radiographs of the lumbar spine at both baseline and follow-up (average time of follow-up, 6.5 yr) and frozen blood samples, taken at baseline. One hundred and seventy-eight men (45 cases) and 454 women (115 cases) were thus selected. Serum estradiol, SHBG, testosterone, and insulin were measured, along with bone mineral density at both spine and hip. Women in the lowest tertile of serum estradiol (< or =15.5 pmol/liter) had a 2.1 times increased risk (95% confidence interval, 1.3-3.5) of incident vertebral fractures, independently of bone mineral density measured at either site. SHBG levels in the lowest two tertiles were associated with a 50% reduction in incident vertebral fracture risk. Women with a combination of both low estradiol and high SHBG had a 7.8 times higher risk of an incident vertebral fracture (95% confidence interval, 2.7-22.5; P < 0.001), adjusted for age and weight. This increased risk did not change when non-SHBG-bound estradiol was used instead of total estradiol. For men, no clear association was found, possibly due to insufficient power. No clear association between testosterone and incident vertebral fractures was observed in either men or women.

Height in pre- and postmenopausal women is influenced by estrogen receptor alpha gene polymorphisms (Article)

2004-01-01T00:00:00Z

The estrogen receptor alpha gene (ESR1) is known to be involved in metabolic pathways influencing growth. We have performed two population-based association studies using three common polymorphisms within this candidate gene to determine whether these are associated with variation in adult stature. In 607 women, aged 55-80 yr, from the Rotterdam Study, the ESR1 PvuII-XbaI haplotype 1 (px) and the L allele of the TA repeat polymorphism (<18 TA repeats) were significantly associated with an allele dose-dependent decrease in height. The per allele copy of ESR1 PvuII-XbaI haplotype 1 height was 0.9 cm shorter (P trend = 0.02) and 1.0 cm/allele copy of the TA repeat L allele (P trend = 0.003). These results were independent of age, age at menarche and menopause, and lumbar spine bone mineral density and remained significant after participants with vertebral fractures were excluded. In 483 men from the Rotterdam Study we found no association with height. In 1500 pre- and perimenopausal women from the Eindhoven Study a similar association was observed; women were 0.5 cm shorter per allele copy of the ESR1 haplotype 1 (P for trend = 0.03). In conclusion, we demonstrate a role for genetic variations in the estrogen receptor alpha gene in determining adult stature in women.

Homocysteine levels and the risk of osteoporotic fracture (Article)

2004-01-01T00:00:00Z

BACKGROUND: Very high plasma homocysteine levels are characteristic of homocystinuria, a rare autosomal recessive disease accompanied by the early onset of generalized osteoporosis. We therefore hypothesized that mildly elevated homocysteine levels might be related to age-related osteoporotic fractures. METHODS: We studied the association between circulating homocysteine levels and the risk of incident osteoporotic fracture in 2406 subjects, 55 years of age or older, who participated in two separate prospective, population-based studies. In the Rotterdam Study, there were two independent cohorts: 562 subjects in cohort 1, with a mean follow-up period of 8.1 years; and 553 subjects in cohort 2, with a mean follow-up period of 5.7 years. In the Longitudinal Aging Study Amsterdam, there was a single cohort of 1291 subjects, with a mean follow-up period of 2.7 years. Multivariate Cox proportional-hazards regression models were used for analysis of the risk of fracture, with adjustment for age, sex, body-mass index, and other characteristics that may be associated with the risk of fracture or with increased homocysteine levels. RESULTS: During 11,253 person-years of follow-up, osteoporotic fractures occurred in 191 subjects. The overall multivariable-adjusted relative risk of fracture was 1.4 (95 percent confidence interval, 1.2 to 1.6) for each increase of 1 SD in the natural-log-transformed homocysteine level. The risk was similar in all three cohorts studied, and it was also similar in men and women. A homocysteine level in the highest age-specific quartile was associated with an increase by a factor of 1.9 in the risk of fracture (95 percent confidence interval, 1.4 to 2.6). The associations between homocysteine levels and the risk of fracture appeared to be independent of bone mineral density and other potential risk factors for fracture. CONCLUSIONS: An increased homocysteine level appears to be a strong and independent risk factor for osteoporotic fractures in older men and women.

Association of 5' estrogen receptor alpha gene polymorphisms with bone mineral density, vertebral bone area and fracture risk (Article)

2003-07-15T00:00:00Z

This study investigates the influence of genetic variation of the estrogen receptor alpha (ESR1) gene locus on several bone parameters in 2042 individuals of The Rotterdam Study, a prospective population-based cohort study of elderly subjects. We analysed three polymorphic sites in the 5' region of the ESR1 gene; a (TA)(n)-repeat in the promoter region, and molecular haplotypes of the PvuII and XbaI RFLPs in intron 1, and inferred long-range haplotypes (LRH) thereof. We observed only three of the possible four PvuII-XbaI haplotypes in our population. A comparison with other Caucasian populations showed similar haplotype frequencies, while in Asian and African populations these were different. Linkage disequilibrium (LD) analysis between the PvuII-XbaI haplotype and the (TA)(n) repeat showed strong LD between the two sites. Reconstruction of long range haplotypes over the entire 5' region, revealed six frequent LRH. In men, we did not observe an association between the ESR1 polymorphisms studied and bone parameters. In women, we demonstrated an allele dose effect of haplotype "px" (P=0.003) and a low number of (TA)(n) repeats (P=0.008) with decreased lumbar spine bone mineral density (BMD) (4.8% lower BMD in women homozygous for haplotype "px", representing 28% of the population, compared with homozygous non-carriers) and decreased vertebral bone area (2.3% difference between extreme genotypes; P=0.016). Most importantly, we found an increased vertebral fracture risk with evidence for an allele dose effect with an odds ratio of 2.2 (95%CI 1.3-3.5) for haplotype "px", and 2.0 (1.5-3.2) for a low number of (TA)(n) repeats. The ESR1 genotype dependent fracture risk is largely independent of BMD and bone area. Combination of risk alleles at both loci by long-range haplotyping improved the associations slightly, but because of the strong LD between the two polymorphic sites, we were unable to determine if any particular polymorphic site is driving the associations found. We conclude that ESR1 polymorphism in the 5' (promoter) region is associated with vertebral fracture risk, lumbar spine BMD and vertebral bone area in postmenopausal women, but not in men. The molecular mechanism underlying this association needs further study.

Interaction between vitamin D receptor genotype and estrogen receptor alpha genotype influences vertebral fracture risk (Article)

2003-01-01T00:00:00Z

In view of the interactions of vitamin D and the estrogen endocrine system, we studied the combined influence of polymorphisms in the estrogen receptor (ER) alpha gene and the vitamin D receptor (VDR) gene on the susceptibility to osteoporotic vertebral fractures in 634 women aged 55 yr and older. Three VDR haplotypes (1, 2, and 3) of the BsmI, ApaI, and TaqI restriction fragment length polymorphisms and three ERalpha haplotypes (1, 2, and 3) of the PvuII and XbaI restriction fragment length polymorphisms were identified. We captured 131 nonvertebral and 85 vertebral fracture cases during a mean follow-up period of 7 yr. ERalpha haplotype 1 was dose-dependently associated with increased vertebral fracture risk (P < 0.001) corresponding to an odds ratio of 1.9 [95% confidence interval (CI), 0.9-4.1] per copy of the risk allele. VDR haplotype 1 was overrepresented in vertebral fracture cases. There was a significant interaction (P = 0.01) between ERalpha haplotype 1 and VDR haplotype 1 in determining vertebral fracture risk. The association of ERalpha haplotype 1 with vertebral fracture risk was only present in homozygous carriers of VDR haplotype 1. The risk of fracture was 2.5 (95% CI, 0.6-9.9) for heterozygous and 10.3 (95% CI, 2.7-40) for homozygous carriers of ERalpha haplotype 1. These associations were independent of bone mineral density. In conclusion, interaction between ERalpha and VDR gene polymorphisms leads to increased risk of osteoporotic vertebral fractures in women, largely independent of bone mineral density.

Thiazide diuretics and the risk for hip fracture (Article)

2003-01-01T00:00:00Z

BACKGROUND: Since most hip fractures are related to osteoporosis, treating accelerated bone loss can be an important strategy to prevent hip fractures. Thiazides have been associated with reduced age-related bone loss by decreasing urinary calcium excretion. OBJECTIVE: To examine the association between dose and duration of thiazide diuretic use and the risk for hip fracture and to study the consequences of discontinuing use. DESIGN: Prospective population-based cohort study. SETTING: The Rotterdam Study. PARTICIPANTS: 7891 individuals 55 years of age and older. MEASUREMENTS: Hip fractures were reported by the general practitioners and verified by trained research assistants. Details of all dispensed drugs were available on a day-to-day basis. Exposure to thiazides was divided into 7 mutually exclusive categories: never use, current use for 1 to 42 days, current use for 43 to 365 days, current use for more than 365 days, discontinuation of use since 1 to 60 days, discontinuation of use since 61 to 120 days, and discontinuation of use since more than 120 days. RESULTS: 281 hip fractures occurred. Relative to nonuse, current use of thiazides for more than 365 days was statistically significantly associated with a lower risk for hip fracture (hazard ratio, 0.46 [95% CI, 0.21 to 0.96]). There was no clear dose dependency. This lower risk disappeared approximately 4 months after thiazide use was discontinued. CONCLUSIONS: Thiazide diuretics protect against hip fracture, but this protective effect disappears within 4 months after use is discontinued.

Osteoporosis: more than fractures alone : an epidemiological approach (Doctoral Thesis)

2002-09-18T00:00:00Z

The main purposes of this thesis are to study the incidence of and risk factors for vertebral fractures and to evaluate the interrelations between bone mineral density, atherosclerosis and breast cancer, all of which are considered to be influenced by estrogen exposure. We will look into fracture prevention; are the current methods for identifying subjects at risk for fractures adequate and should men and women be treated equally. Finally, the results of these studies are combined in a model on cost-effectiveness of fracture prevention In Chapter 2, vertebral fractures are investigated in both men and women. In chapter 2.1, the incidence of vertebral fractures will be described. In addition, the associations of incident vertebral fractures with both BMD and the presence of baseline prevalent vertebral fractures are studied. In chapter 2.2, we extended the analyses on risk factors for incident vertebral fractures for men and women. At first, we evaluated potential risk factors univariately for an association \Vith incident vertebral fractures. Then, we evaluated whether univariately sigoificant risk factors were independent from BMD, prevalent vertebral fractures and from each other. In Chapter 3, we study the value of a T -score of BMD in fracture prevention. In Chapter 3.1 it is evaluated whether the current criterion for osteoporosis, as defined by the 'WHO, of a T-score at or below -2.5, is useful in accurately identifying women who will fracture within the coming years. Chapter 3.2 discusses whether the association between BMD and fractures is similar for both men and women and if so, whether using a gender specific T -score of BMD is useful in describing the problem of osteoporosis in men. Chapter 4 describes the associations between BMD and diseases other than osteoporosis that are also considered to be influenced by estrogen exposure. First, in Chapter 4.1, the association between BMD and peripheral arterial disease, which is a measure for generalised atherosclerosis, is described. Chapter 4.2 then shows the association between BMD and incident breast cancer in women. Following the associations between BMD and morbidity, the association between femoral neck BMD and overall mortality is described for both men and women in Chapter 5. The results of a mathematical model on the cost-effectiveness of fracture prevention are discussed in Chapter 6. This model is an example of how the results as described in the previous chapters can be used to evaluate the costeffectiveness of fracture prevention. In this model, different treatment strategies ofHRT, SERMs and bisphosphonates are compared. Finally, in Chapter 7 the overall results of this thesis are placed in perspective in a general discussion. We further discuss pitfalls, as well as the clinical relevance of the research that was presented in this thesis. The general discussion ends with some suggestions for further research.