Population differences in completeness and reliability of Dutch COVID-19 registry data: The influence of testing policy, test readiness, and registration policy from an epidemiological perspective

During the COVID-19 pandemic, the bidirectional relationship between policy and data reliability has been a challenge for researchers of the local municipal health services. Policy decisions on population specific test locations and selective registration of negative test results led to population differences in data quality. This hampered the calculation of reliable population specific infection rates needed to develop proper data driven public health policy.

[Population differences in the completeness and reliability of COVID-19 registration data]

During the COVID-19 pandemic, the bidirectional relationship between policy and data reliability has been a challenge for researchers of the local municipal health services. Policy decisions on population specific test locations and selective registration of negative test results led to population differences in data quality. This hampered the calculation of reliable population specific infection rates needed to develop proper data driven public health policy.

Dietary patterns and changes in frailty status: the Rotterdam study

PURPOSE

To determine the associations between a priori and a posteriori derived dietary patterns and a general state of health, measured as the accumulation of deficits in a frailty index.

METHODS

Cross-sectional and longitudinal analysis embedded in the population-based Rotterdam Study (n = 2632) aged 45 years. Diet was assessed at baseline (year 2006) using food frequency questionnaires. Dietary patterns were defined a priori using an existing index reflecting adherence to national dietary guidelines and a posteriori using principal component analysis. A frailty index was composed of 38 health deficits and measured at baseline and follow-up (4 years later). Linear regression analyses were performed using adherence to each of the dietary patterns as exposure and the frailty index as outcome (all in Z-scores).

RESULTS

Adherence to the national dietary guidelines was associated with lower frailty at baseline (β -0.05, 95% CI -0.08, -0.02). Additionally, high adherence was associated with lower frailty scores over time (β -0.08, 95% CI -0.12, -0.04). The PCA revealed three dietary patterns that we named a "Traditional" pattern, high in legumes, eggs and savory snacks; a "Carnivore" pattern, high in meat and poultry; and a "Health Conscious" pattern, high in whole grain products, vegetables and fruit. In the cross-sectional analyses adherence to these patterns was not associated with frailty. However, adherence to the "Traditional" pattern was associated with less frailty over time (β -0.09, 95% CI -0.14, -0.05).

CONCLUSION

No associations were found for adherence to a "healthy" pattern or "Carnivore" pattern. However, Even in a population that is relatively young and healthy, adherence to dietary guidelines or adherence to the Traditional pattern could help to prevent, delay or reverse frailty levels.

Fracture incidence and secular trends between 1989 and 2013 in a population based cohort: The Rotterdam Study

Fracture incidence needs to be evaluated over time to assess the impact of the enlarging population burden of fractures (due to increase in lifespan) and the efficacy of fracture prevention strategies. Therefore, we aimed to evaluate the association of femoral neck bone mineral density (FN-BMD) measured using dual-energy X-ray absorptiometry (DXA) at baseline with fracture risk over a long follow-up time period. Incident non-vertebral fractures were assessed in 14,613 individuals participating in the Rotterdam Study with up to 20 years of follow-up. During a mean follow-up of 10.7 ± 6.2 years, 2971 (20.3%) participants had at least one incident non-vertebral fracture. The risk for any non-vertebral fracture was 1.37 (95% Confidence Interval (CI): 1.25-1.49) and 1.42 (95%CI: 1.35-1.50) for men and women, respectively. The majority (79% in men and 75% in women) of all fractures occurred among participants a normal or osteopenic T-score. The incidence rates per 1000 person-years for the most common fractures were 5.3 [95%CI: 5.0-5.7] for hip, 4.9 [95%CI: 4.6-5.3] for wrist and 2.3 [95%CI: 2.0-2.5] for humerus. To examine the predictive ability of BMD through follow-up time we determined fracture hazard ratios (HR) per standard deviation decrease in femoral neck BMD across five year bins. No differences were observed, with a HR of 2.5 (95%CI: 2.0-3.1) after the first 5 years, and of 1.9 (95%CI: 1.1-3.3) after 20 years. To assess secular trends in fracture incidence at all skeletal sites we compared participants at an age of 70-80 years across two time periods: 1989-2001 (n = 2481, 60% women) and 2001-2013 (n = 2936, 58% women) and found no statistically significant difference (p < 0.05) between fracture incidence rates (i.e., incidence of non-vertebral fractures of 26.4 per 1000 PY [95%CI: 24.4-28.5]) between 1989 and 2001, and of 25.4 per 1000 PY [95%CI: 23.0-28.0] between 2001 and 2013. In conclusion, BMD is still predictive of future fracture over a long period of time. While no secular changes in fractures rates seem to be observed after a decade, the majority of fractures still occur above the osteoporosis threshold, emphasizing the need to improve the screening of osteopenic patients.

Genome-Wide Interactions with Dairy Intake for Body Mass Index in Adults of European Descent

SCOPE

Body weight responds variably to the intake of dairy foods. Genetic variation may contribute to inter-individual variability in associations between body weight and dairy consumption.

METHODS AND RESULTS

A genome-wide interaction study to discover genetic variants that account for variation in BMI in the context of low-fat, high-fat and total dairy intake in cross-sectional analysis was conducted. Data from nine discovery studies (up to 25 513 European descent individuals) were meta-analyzed. Twenty-six genetic variants reached the selected significance threshold (p-interaction <10-7) , and six independent variants (LINC01512-rs7751666, PALM2/AKAP2-rs914359, ACTA2-rs1388, PPP1R12A-rs7961195, LINC00333-rs9635058, AC098847.1-rs1791355) were evaluated meta-analytically for replication of interaction in up to 17 675 individuals. Variant rs9635058 (128 kb 3' of LINC00333) was replicated (p-interaction = 0.004). In the discovery cohorts, rs9635058 interacted with dairy (p-interaction = 7.36 × 10-8) such that each serving of low-fat dairy was associated with 0.225 kg m-2 lower BMI per each additional copy of the effect allele (A). A second genetic variant (ACTA2-rs1388) approached interaction replication significance for low-fat dairy exposure.

CONCLUSION

Body weight responses to dairy intake may be modified by genotype, in that greater dairy intake may protect a genetic subgroup from higher body weight.

Dietary patterns in an elderly population and their relation with bone mineral density: the Rotterdam Study

Purpose

Our aim was to identify dietary patterns that are associated with bone mineral density (BMD) against a background of relatively high dairy intake in elderly Dutch subjects.

Methods

Participants were 55 years of age and older (n = 5144) who were enrolled in The Rotterdam Study, a population-based prospective cohort study. Baseline intake of 28 pre-defined food groups was determined using a validated food frequency questionnaire. Dietary patterns were identified using principal component analysis. BMD was measured using dual-energy X-ray absorptiometry at baseline and at three subsequent visits (between 1993 and 2004). Linear mixed modelling was used to longitudinally analyse associations of adherence to each pattern with repeatedly measured BMD (both in Z scores).

Results

After adjustment for confounders, two dietary patterns were associated with high BMD: a “Traditional” pattern, characterized by high intake of potatoes, meat and fat (β = 0.06; 95 % CI 0.03, 0.09) and a “Health conscious” pattern, characterized by high intake of fruits, vegetables, poultry and fish (β = 0.06; 95 % CI 0.04, 0.08). The “Processed” pattern, characterized by high intake of processed meat and alcohol, was associated with low BMD (β = −0.03; 95 % CI −0.06, −0.01). Associations of adherence to the “Health conscious” and “Processed” pattern with BMD were independent of body weight and height, whereas the association between adherence to the “Traditional” pattern with BMD was not.

Conclusions

Against a background of high dairy intake and independent of anthropometrics, a “Health conscious” dietary pattern may have benefits for BMD, whereas a “Processed” dietary pattern may pose a risk for low BMD.

Electronic supplementary material

The online version of this article (doi:10.1007/s00394-016-1297-7) contains supplementary material, which is available to authorized users.

The Influence of Serum Uric Acid on Bone Mineral Density, Hip Geometry, and Fracture Risk: The Rotterdam Study

CONTEXT

The role of uric acid (UA) in skeletal metabolism remains to be unraveled.

OBJECTIVE

We prospectively investigated the association between UA, bone mineral density at the femoral neck (FN-BMD), hip bone geometry parameters, and incident fracture risk and examined whether the associations were modified by age and vitamin C intake.

PARTICIPANTS AND SETTING

Data of 5074 participants of The Rotterdam Study, a prospective population-based cohort.

EXPOSURE

Serum UA was assessed at baseline.

MAIN OUTCOMES AND MEASURES

FN-BMD was measured at baseline, and at second, third, and fourth visits of the Rotterdam Study. Hip bone geometry parameters were measured at baseline and at the second and third visits.

RESULTS

Serum UA levels (per SD increase) were positively associated with FN-BMD (β = 0.007 g/cm(2); 95% confidence interval [CI] = 0.002-0.01), thicker cortices (β = 0.002 cm; 95% CI = 0.0003-0.002), lower bone width (β = -0.013 cm; 95% CI = -0.23 to -0.003), and lower cortical buckling ratio (β = -0.19; 95% CI = -0.33 to -0.06). The effects of UA on FN-BMD and cortical buckling ratio tended to become stronger over time. Hazard ratios and 95% CIs per SD increase of baseline UA levels for the development of any type of incident fractures, nonvertebral fractures, and osteoporotic fractures were 0.932 (0.86-0.995), 0.924 (0.856-0.998), and 0.905 (0.849-0.982), respectively. These associations were more prominent in older individuals (age, >65 y) and in participants with high intakes of vitamin C (> median).

CONCLUSIONS

Higher levels of serum UA are associated with higher BMD (at the expense of thicker cortices and narrower bone diameters) and may be a protective factor in bone metabolism. However, interactions with age and vitamin C may be present.

Macronutrient composition and gestational weight gain: a systematic review

BACKGROUND

Abnormal gestational weight gain is associated with unfavorable pregnancy outcomes. Several risk factors have been identified, but the effect of macronutrient intake during pregnancy on gestational weight gain has not been systematically evaluated in both high-income countries and low- and middle-income countries.

OBJECTIVE

We conducted a systematic review of the literature in 8 different databases (until 12 August 2015) to assess whether energy intake and macronutrient intake (i.e., protein, fat, and carbohydrate) during pregnancy were associated with gestational weight gain (following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines).

RESULTS

Of 7623 identified references, we included 56 articles (46 observational studies and 10 trials, 28 of which were in high-income countries and 28 of which were in low- and middle-income countries). Eleven of the included articles were of high quality (20%). Results of 5 intervention and 7 high-quality observational studies suggested that higher energy intake during pregnancy is associated with higher gestational weight gain (n = 52). Results from observational studies were inconsistent for protein intake (n = 29) and carbohydrate intake (n = 18). Maternal fat intake (n = 25) might be associated with gestational weight gain as suggested by observational studies, although the direction of this association might depend on specific types of fat (e.g., saturated fat). Macronutrient intake was not consistently associated with the prevalence of inadequate or excessive gestational weight gain. Associations were comparable for high-income countries and low- and middle-income countries.

CONCLUSIONS

The current literature provides evidence that energy intake is associated with gestational weight gain, but the roles of individual macronutrients are inconsistent. However, there is a need for higher-quality research because the majority of these studies were of low quality.

Dietary acid load in early life and bone health in childhood: the Generation R Study

BACKGROUND

Dietary contribution to acid-base balance in early life may influence subsequent bone mineralization. Previous studies reported inconsistent results regarding the associations between dietary acid load and bone mass.

OBJECTIVE

We examined the associations of dietary acid load in early life with bone health in childhood.

DESIGN

In a prospective, multiethnic, population-based cohort study of 2850 children, we estimated dietary acid load as dietary potential renal acid load (dPRAL), based on dietary intakes of calcium, magnesium, phosphorus, potassium, and protein, and as a protein intake to potassium intake ratio (Pro:K) at 1 y of age and in a subgroup at 2 y of age : Bone mineral density, bone mineral content (BMC), area-adjusted BMC, and bone area were assessed by dual-energy X-ray absorptiometry at the median age of 6 y. Data were analyzed by using multivariable linear regression models.

RESULTS

After adjusting for relevant maternal and child factors, dietary acid load estimated as either dPRAL or Pro:K ratio was not consistently associated with childhood bone health. Associations did not differ by sex, ethnicity, weight status, or vitamin D supplementation. Only in those children with high protein intake in our population (i.e., >42 g/d), a 1-unit increase in dPRAL (mEq/d) was inversely associated with BMC (difference: -0.32 g; 95% CI: -0.64, -0.01 g).

CONCLUSIONS

Dietary acid load in early life was not consistently associated with bone health in childhood. Further research is needed to explore the extent to which dietary acid load in later childhood may affect current and future bone health.