G. K. R. Berntsen

Features of the metabolic syndrome and the risk of non-vertebral fractures : The Tromso Study

Owing to a technical error, a number of non-vertebral fractures had not been included in the database. Owing to changes in the informed consents for some of the participants, at the time of repeated analyses, the study cohort changed from 27,159 to 26,905 participants. A total of 1,882 non-vertebral fractures (not 1,249 as stated in the publication) were registered. After excluding all subjects with missed measurements of any metabolic syndrome criteria (n=152), 750 men and 1108 women (not 438 men and 789 women as stated in the publication) suffered non-vertebral fractures. The risk estimates of the associations between having three or more of the metabolic syndrome criteria and nonvertebral fractures and changed to (RR 0.81, 95% CI 0.64– 1.04) in men and (RR 0.78, 95% CI 0.65–0.93) in women. The trend towards reduced fracture risk by increasing mean BP in men was no longer significant (Fig. 2). We apologize for any inconvenience caused by this unfortunate error. Osteoporos Int (2009) 20:839 DOI 10.1007/s00198-009-0847-8

Reference ranges for serial measurements of blood velocity and pulsatility index at the intra‐abdominal portion, and fetal and placental ends of the umbilical artery

To construct reference ranges for serial measurements of umbilical artery (UA) blood flow velocity and pulsatility index (PI) at standardized insonation sites during the second half of pregnancy.

What do Norwegian women and men know about osteoporosis

A survey of a random sample of 1514 Norwegian women and men aged 16–79 years was undertaken to investigate knowledge of osteoporosis and attitudes towards methods for preventing this disease. The interviews were carried out by Central Bureau of Statistics of Norway as part of their monthly national poll using a structured questionnaire. Women knew more about osteoporosis than did men (p<01). In both men and women increased knowledge of osteoporosis was correlated to a high level of education. Furthermore it was clearly demonstrated that knowing someone with osteoporosis or suffering from it oneself increased the knowledge of osteoporosis significantly in both women and men. Multiple regression analysis confirmed the univariate analyses, and education was the strongest predictive factor for knowledge. To a hypothetical question as many as two-thirds of the women answered that they would use long-term hormone replacement therapy (HRT) to prevent osteoporosis on the recommendation of their general practitioner. Their attitudes towards the use of estrogen therapy did not show any significant relation to age, but their reluctance towards HRT increased with education (p<001). When asked a question about their preferences regarding the use of physical activity as a means to prevent osteoporosis, older women preferred walking (p<.001), whereas younger women wanted more organized athletic activity (p<001). The data demonstrated that there was a high degree of general knowledge of osteoporosis and its consequences in the general population.

A prospective study of sex steroids, sex hormone-binding globulin, and non-vertebral fractures in women and men : the Tromsø Study

OBJECTIVES As bone fragility is partly the result of sex hormone deficiency, we sought to determine whether circulating sex steroids or sex hormone-binding globulin (SHBG) predicts non-vertebral fractures. METHODS Forearm bone mineral density (BMD), total estradiol and testosterone, calculated free levels, and SHBG were measured in 1386 postmenopausal women and 1364 men aged 50-84 years at baseline in the Tromsø Study (1994-1995). Non-vertebral fractures were documented between 1994 and 2005. RESULTS During 8.4 years (range 0.01-10.4) of follow-up, 281 women and 105 men suffered non-vertebral fractures. For both sexes, fracture cases had lower BMD and higher SHBG, but sex steroids were not lower. Each standard deviation (s.d.) increase in SHBG increased non-vertebral fracture risk in women (hazards ratio (HR) 1.17; 95% confidence interval (CI) 1.03-1.33) and men (HR 1.26; 95% CI 1.03-1.54). After further adjustment for BMD, the risk was not statistically significant in women (HR 1.09; 95% CI 0.95-1.24) or men (HR 1.22; 95% CI 0.99-1.49). Each s.d. decrease in BMD increased fracture risk in women (HR 1.36; 95% CI 1.19-1.56) and men (HR 1.41; 95% CI 1.15-1.73). Fracture rates were highest in participants with SHBG in the highest tertile and BMD in the lowest tertile and were 37.9 and 17.0 per 1000 person-years in women and men respectively. However, in both sexes the combination of BMD and SHBG was no better predictor of fracture risk than BMD alone. Sex steroids were not associated with fracture risk. CONCLUSIONS Measurements of sex steroids or SHBG are unlikely to assist in decision making regarding fracture risk susceptibility.

The Tromsø Study: Artifacts in Forearm Bone Densitometry – Prevalence and Effects

Abstract: Suboptimal performance of bone densitometer, operator and/or subject may cause artifacts of consequence both for individual patient management and research. The prevalence and effects of such artifacts are largely unknown in densitometry. A cross-sectional population-based study was carried out of artifacts in forearm bone densitometry with single X-ray Absorptiometry (SXA) of the nondominant hand (distal and ultradistal site). After the screening, all scans were reviewed for artifact detection and reanalysis. The effect on the bone mineral density (BMD) result was found by comparing artifactual scans with a reanalyzed version or with normal repeat scans. All women aged 50–74 years, all men aged 55–74 years and 5–10% samples of other age groups aged ≥25 years attending the fourth Tromsø health study were invited to have bone densitometry. The response rate from the background population was 80% (n= 7948). Fourteen percent of subjects had a movement artifact at either the distal or ultradistal site. The individual BMD variation was twice as large in scans with a movement artifact (0.94%) compared with normal scans (0.58%) (p= 0.0027). The radial endplate was inaccurately detected in 74% of the scans. Reanalysis of these scans led to a mean 3.8% decrease in the BMD value and an increase in the prevalence of osteoporosis of 10%. Artifacts were thus common, and their effects were clinically relevant in forearm bone densitometry. Artifacts and their effects need to be characterized in other bone densitometry settings also.

The Tromsø study: determinants of precision in bone densitometry.

Studies of precision determinants in bone densitometry are scarce. A total of 111 subjects recruited from the population-based multipurpose Tromsø Study (Norway), 27-75 years of age, had repeated forearm bone single X-ray absorptiometry (SXA) measurements. Measurement conditions were systematically varied in series up to eight scans. Median coefficients of variation (CV) for two scans performed 1 week apart, by two different operators were 0.79% and 0.98% at distal and ultradistal sites, respectively. The CV distribution was skewed: 5% of the subjects had individual CVs above 2.2% (distal) and 3.4% (ultradistal). Age (P = 0.0097) and repositioning were important determinants of precision. The SXA bone mineral density (BMD)-measurement method is sufficiently precise to establish BMD level. The minimal individual percentage BMD change that can be detected with 95% certainty was 2% and 3% at distal and ultradistal sites, respectively. Detection of BMD changes less than this should rely on multiple repeat measurements at each point in time.

Electronic Symptom Reporting Between Patient and Provider for Improved Health Care Service Quality: A Systematic Review of Randomized Controlled Trials. Part 1: State of the Art

Background Over the last two decades, the number of studies on electronic symptom reporting has increased greatly. However, the field is very heterogeneous: the choices of patient groups, health service innovations, and research targets seem to involve a broad range of foci. To move the field forward, it is necessary to build on work that has been done and direct further research to the areas holding most promise. Therefore, we conducted a comprehensive review of randomized controlled trials (RCTs) focusing on electronic communication between patient and provider to improve health care service quality, presented in two parts. Part 2 investigates the methodological quality and effects of the RCTs, and demonstrates some promising benefits of electronic symptom reporting. Objective To give a comprehensive overview of the most mature part of this emerging field regarding (1) patient groups, (2) health service innovations, and (3) research targets relevant to electronic symptom reporting. Methods We searched Medline, EMBASE, PsycINFO, Cochrane Central Register of Controlled Trials, and IEEE Xplore for original studies presented in English-language articles published from 1990 to November 2011. Inclusion criteria were RCTs of interventions where patients or parents reported health information electronically to the health care system for health care purposes and were given feedback. Results Of 642 records identified, we included 32 articles representing 29 studies. The included articles were published from 2002, with 24 published during the last 5 years. The following five patient groups were represented: respiratory and lung diseases (12 studies), cancer (6), psychiatry (6), cardiovascular (3), and diabetes (1). In addition to these, 1 study had a mix of three groups. All included studies, except 1, focused on long-term conditions. We identified four categories of health service innovations: consultation support (7 studies), monitoring with clinician support (12), self-management with clinician support (9), and therapy (1). Most of the research (21/29, 72%) was conducted within four combinations: consultation support innovation in the cancer group (5/29, 17%), monitoring innovation in the respiratory and lung diseases group (8/29, 28%), and self-management innovations in psychiatry (4/29, 14%) and in the respiratory and lung diseases group (4/29, 14%). Research targets in the consultation support studies focused on increased patient centeredness, while monitoring and self-management mainly aimed at documenting health benefits. All except 1 study aiming for reduced health care costs were in the monitoring group. Conclusion RCT-based research on electronic symptom reporting has developed enormously since 2002. Research including additional patient groups or new combinations of patient groups with the four identified health service innovations can be expected in the near future. We suggest that developing a generic model (not diagnosis specific) for electronic patient symptom reporting for long-term conditions may benefit the field.

Circulating Sex Steroids, Sex Hormone-Binding Globulin, and Longitudinal Changes in Forearm Bone Mineral Density in Postmenopausal Women and Men: The Tromsø Study

Bone loss during advancing age in women and men is partly the result of sex steroid deficiency. As the contribution of circulating sex steroids and sex hormone-binding globulin (SHBG) to bone loss remains uncertain, we sought to determine whether levels of sex steroids or SHBG predict change in bone mineral density (BMD) in women and men. A population-based study in the city of Tromsø of 6.5 years’ duration (range 5.4-7.4) included 927 postmenopausal women aged 37–80 years and 894 men aged 25–80 years. Total estradiol and testosterone, calculated free levels, and SHBG were measured at baseline, and BMD change at the distal forearm was determined using BMD measurements in 1994–1995 and 2001. Bone loss was detected in postmenopausal women and men. Free estradiol and SHBG predicted age-adjusted bone loss in postmenopausal women, but only free estradiol was associated after further adjustment for body mass index and smoking in mixed models (P < 0.05). After same adjustment, only SHBG persisted as a significant independent predictor of bone loss in men (P < 0.001). However, only 1% of the variance in bone loss was accounted for by these measurements. We therefore conclude that the relations between sex steroids and bone loss are weak and measurements of sex steroids are unlikely to assist in clinical decision making.

Electronic Symptom Reporting Between Patient and Provider for Improved Health Care Service Quality: A Systematic Review of Randomized Controlled Trials. Part 2: Methodological Quality and Effects

Background We conducted in two parts a systematic review of randomized controlled trials (RCTs) on electronic symptom reporting between patients and providers to improve health care service quality. Part 1 reviewed the typology of patient groups, health service innovations, and research targets. Four innovation categories were identified: consultation support, monitoring with clinician support, self-management with clinician support, and therapy. Objective To assess the methodological quality of the RCTs, and summarize effects and benefits from the methodologically best studies. Methods We searched Medline, EMBASE, PsycINFO, Cochrane Central Register of Controlled Trials, and IEEE Xplore for original studies presented in English-language articles between 1990 and November 2011. Risk of bias and feasibility were judged according to the Cochrane recommendation, and theoretical evidence and preclinical testing were evaluated according to the Framework for Design and Evaluation of Complex Interventions to Improve Health. Three authors assessed the risk of bias and two authors extracted the effect data independently. Disagreement regarding bias assessment, extraction, and interpretation of results were resolved by consensus discussions. Results Of 642 records identified, we included 32 articles representing 29 studies. No articles fulfilled all quality requirements. All interventions were feasible to implement in a real-life setting, and theoretical evidence was provided for almost all studies. However, preclinical testing was reported in only a third of the articles. We judged three-quarters of the articles to have low risk for random sequence allocation and approximately half of the articles to have low risk for the following biases: allocation concealment, incomplete outcome data, and selective reporting. Slightly more than one fifth of the articles were judged as low risk for blinding of outcome assessment. Only 1 article had low risk of bias for blinding of participants and personnel. We excluded 12 articles showing high risk or unclear risk for both selective reporting and blinding of outcome assessment from the effect assessment. The authors’ hypothesis was confirmed for 13 (65%) of the 20 remaining articles. Articles on self-management support were of higher quality, allowing us to assess effects in a larger proportion of studies. All except one self-management interventions were equally effective to or better than the control option. The self-management articles document substantial benefits for patients, and partly also for health professionals and the health care system. Conclusion Electronic symptom reporting between patients and providers is an exciting area of development for health services. However, the research generally is of low quality. The field would benefit from increased focus on methods for conducting and reporting RCTs. It appears particularly important to improve blinding of outcome assessment and to precisely define primary outcomes to avoid selective reporting. Supporting self-management seems to be especially promising, but consultation support also shows encouraging results.

Doppler-derived umbilical artery absolute velocities and their relationship to fetoplacental volume blood flow: a longitudinal study

To construct reference ranges for serial measurements of the umbilical artery (UA) absolute blood flow velocities in the second half of pregnancy and to test the hypothesis that significant associations exist between UA velocities and placental volume blood flow assessed from umbilical vein blood flow velocities and diameter.