AB0384 THE EFFECT OF A LIFESTYLE PROGRAM ON PATIENTS AT RISK FOR RHEUMATOID ARTHRITIS:THE “PLANTS FOR JOINTS” PILOT RANDOMIZED CLINICAL TRIAL

Background

An unhealthy lifestyle increases the risk of developing rheumatoid arthritis (RA). Interventions including plant-based diets, physical activity, and stress management have shown benefits for RA patients but have not yet been evaluated in a program for patients at risk for RA.

Objectives

To investigate preliminary effectiveness of a multidisciplinary lifestyle program on RA risk in patients at risk for RA, in comparison to usual care.

Methods

In the “Plants for Joints” (PFJ) pilot RCT, patients with anti-citrullinated protein antibody (ACPA) positive arthralgia were randomized to the PFJ or control group. Both groups received usual care while the PFJ group additionally followed a 16-week lifestyle program based on a whole food plant-based diet, physical activity, and stress management.1 The primary outcome was risk of developing RA as quantified by the RA risk score (including family history, symmetry, stiffness, pain level, RF/ACPA level).2 The maximum score (13 points) was given to participants who developed RA. Secondary outcomes included self-reported pain intensity, inflammatory, anthropometric, and metabolic markers, and serum levels of ACPA and rheumatoid factor (RF). A linear mixed model for between group analysis was used, adjusted for baseline values.

Results

14 out of 17 included patients completed the study (all female, mean age 47 years). Three patients (n = 2 PFJ group, n = 1 control group) were diagnosed with RA after mean 9.6 weeks and remained in the study. After 16 weeks there was no significant difference in RA risk score between PFJ and control groups (Figure 1). Compared to the control group, the PFJ group had significantly lower fat mass and LDL-cholesterol after 16 weeks (Table 1). After the intervention the PFJ group had an average weight loss of 4.9 kg, of which 2.7 kg was fat mass.

Table 1.

Results reported as mean (SD) when normally distributed and median [Q1 – Q3] when skewed. P-value <0.05 = significant. RA = rheumatoid arthritis, ACPA = anti-citrullinated protein antibody, RF = Rheumatoid factor, ESR = erythrocyte sedimentation rate, CRP = C-reactive protein.

Plants for Joints group (n = 7)Control group (n = 7)BaselineWeek 16BaselineWeek 16p-valueRA risk and related outcomesRA risk score6.1 (1.4)8.6 (3.4)7.1 (1.4)8.3 (2.3)0.56Pain intensity4.9 (2.6)3.8 (1.9)5.7 (2.6)4.0 (2.1)0.74ACPA, kU/l330 [94 - 530]225 [116 - 550]256 [79 - 462]202 [94 - 403]0.86RF, kU/l13 [3 - 68]11 [3 - 56]12 [3 - 21]5 [4 - 12]0.96RA diagnosis, N0201-InflammationESR, mmol/hour9 [6 - 15]7 [6 - 9]7 [6 - 12]12 [8 -17]0.79CRP, mg/l0.7 [0.6 - 2.5]0.6 [0.6 - 1.2]3.0 [1.1 - 3.6]3.3 [1.3 - 6.7]0.58AnthropometricWeight, kg78.4 (18.6)73.5 (16.4)77.4 (16.2)77.0 (16.3)0.28BMI, kgm-226.8 (5.3)25.1 (4.5)28.2 (6.2)28.0 (6.0)0.23Fat mass, kg30.6 (14.3)27.9 (12.3)31.2 (12.8)29.8 (13.0)<0.01Waist circumference, cm87.9 (13.3)86.6 (11.6)91.6 (15.5)90.6 (16.1)0.33MetabolicLDL-cholesterol, mmol/l3.1 (0.87)2.83 (0.75)3.07 (0.36)3.05 (0.36)<0.01HbA1C, mmol/mol34.9 (3.2)34.4 (3.1)35.1 (3.0)36.9 (3.6)0.97

Conclusion

The results of this pilot study do not suggest the PFJ lifestyle program influenced RA risk score, pain, or autoantibody levels, although possible effects cannot be excluded due to the small sample size. However, metabolic health clearly improved in the PFJ group.

References

[1]Walrabenstein, Trials 2021

[2]van de Stadt, Ann Rheum Dis 2013

Acknowledgements

C. W. was funded by ZonMW (The Netherlands Organization for Health Research and Development) grant number 555003210.

Disclosure of Interests

Carlijn Wagenaar: None declared, Wendy Walrabenstein: None declared, Marieke van der Leeden: None declared, Franktien Turkstra: None declared, Jos Twisk: None declared, Maarten Boers Consultant of: Consultant for Novartis, Henriët van Middendorp: None declared, Peter Weijs: None declared, Dirkjan van Schaardenburg: None declared

AB0396 EFFECT OF A MULTIDISCIPLINARY LIFESTYLE PROGRAM IN PATIENTS WITH RHEUMATOID ARTHRITIS: THE PLANTS FOR JOINTS RANDOMIZED CONTROLLED TRIAL

Background

Lifestyle factors have been associated with the development and progression of rheumatoid arthritis (RA). Interventions involving whole food plant-based diets (WFPDs), physical activity or stress management have shown promising results for people with RA but were not yet evaluated in an integrated program.

Objectives

To determine the effect of a 16-week multidisciplinary lifestyle program on disease activity in patients with RA.

Methods

In the “Plants for Joints” (PFJ) parallel-arm, assessor-blind randomized clinical trial, patients with RA and a 28-joint Disease Activity Score [DAS28] score ≥ 2.6 and ≤ 5.1, were assigned to the PFJ group or the control group. The PFJ group followed a lifestyle program based on a WFPD, physical activity, and stress management in addition to usual care. The control group received usual care. Medication was kept stable three months before and during the trial. Secondary outcomes included anthropometric, and metabolic markers. An intention-to-treat analysis with a linear mixed model, adjusted for baseline values was used to analyze between-group differences of continuous outcomes.

Results

Of 115 people screened, 85 were randomized and 79 completed the study. Participants were 91% female with a mean (SD) age of 55 (12) and body mass index of 26 (4) kg/m2. After 16 weeks the PFJ group had a mean 0.85-point greater improvement of the DAS28 versus the control group (95% CI 0.40 to 1.30; p < 0.001) (Figure 1). Subgroup analyses showed significant improvements in the seropositive as well as the seronegative subgroup, although the effect was more profound in the seronegative group. Weight, fat mass, HbA1c, LDL and triglycerides also showed significant improvements in the PFJ versus control group, while blood glucose and HDL remained unchanged (Table 1). No serious adverse events occurred.

Conclusion

The 16-week PFJ lifestyle program substantially decreased disease activity in people with RA with low-moderate disease activity.

Disclosure of Interests

Wendy Walrabenstein: None declared, Carlijn Wagenaar: None declared, Marike van der Leeden: None declared, Franktien Turkstra: None declared, Jos Twisk: None declared, Maarten Boers Consultant of: Consultant for Novartis, Henriët van Middendorp: None declared, Peter Weijs: None declared, Dirkjan van Schaardenburg: None declared

O-138 Reproductive performance of women with and without intrauterine adhesions following recurrent dilatation and curettage for miscarriage: long-term follow-up of a randomized controlled trial

Study question

Are the long-term reproductive outcomes following recurrent dilatation and curettage (D&C) for miscarriage in women with identified and treated intrauterine adhesions (IUAs) comparable to women without IUAs.

Summary answer

Reproductive outcomes in women with identified and treated IUAs following recurrent D&C for miscarriage are impaired compared to women without IUAs.

What is known already

The Prevention of Adhesions Post Abortion (PAPA) study showed that application of auto-crosslinked hyaluronic acid (ACP) gel, an absorbable barrier in women undergoing recurrent D&C for miscarriage resulted in a lower rate of IUAs, 13% versus 31% (relative risk 0.43, 95% CI 0.22 to 0.83), lower mean adhesion score and significant less moderate to severe IUAs. It is unclear what the impact is of IUAs on long-term reproductive performance.

Study design, size, duration

This was a follow-up of the PAPA study, a multicenter randomized controlled trial evaluating the application of ACP gel in women undergoing recurrent D&C for miscarriage. All included women received a diagnostic hysteroscopy 8–12 weeks after randomization to evaluate the uterine cavity and for adhesiolysis if IUAs were present. Here, we present the reproductive outcomes in women with identified and treated IUAs versus women without IUAs, 46 months after randomization.

Participants/materials, setting, methods

Between December 2011 and July 2015, 152 women with a first-trimester miscarriage with at least one previous D&C, were randomized for D&C alone or D&C with immediate intrauterine application of ACP gel. Participants were approached at least 30 months after randomization to evaluate reproductive performance, obstetric and neonatal outcomes and cycle characteristics. Main outcome was ongoing pregnancy. Outcomes of subsequent pregnancies, time to conception and time to live birth were also recorded.

Main results and the role of chance

In women pursuing a pregnancy, 14/24 (58%) ongoing pregnancies were recorded in women with identified and treated IUAs versus 80/89 (90%) ongoing pregnancies in women without IUAs odds ratio (OR) 0.18 (95% CI 0.06 to 0.50, P-value &lt;0.001). Documented live birth was also lower in women with IUAs; 13/24 (54%) with versus 75/89 (84%) without IUAs, OR 0.22 (95% CI: 0.08 to-0.59, P-value 0.004). The median time to conception was 7 months in women with identified and treated IUAs versus 5 months in women without IUAs (hazard ratio (HR) 0.84 (95% CI 0.54 to 1.33)) and time to conception leading to a live birth 15 months versus 5.0 months (HR 0.54 (95% CI: 0.30 to 0.97)). In women with identified and treated IUAs, premature deliveries were recorded in 3/16 (19%) versus 4/88 (5%) in women without IUAs, P-value 0.01. Complications were recorded in respectively 12/16 (75%) versus 26/88 (30%), P-value 0.001. No differences were recorded in mean birth weight between the groups.

Limitations, reasons for caution

In the original PAPA study, randomization was applied for ACP gel application. Comparing women with and without IUAs is not in line with the randomization and therefore confounding of the results cannot be excluded. IUAs, if visible during routine hysteroscopy after randomization were removed as part of the study protocol.

Wider implications of the findings

As IUAs have an impact on reproductive performance, even after hysteroscopic adhesiolysis, primary prevention is essential. Expectative and medical management should therefore be considered as serious alternatives for D&C in women with a miscarriage. In case D&C is necessary, application of ACP gel should be considered.

Trial registration number

Netherlands Trial Register NTR 3120.

OP0018 A MULTICENTER RANDOMIZED STUDY IN EARLY RHEUMATOID ARTHRITIS TO COMPARE ACTIVE CONVENTIONAL THERAPY VERSUS THREE BIOLOGICAL TREATMENTS: 24 WEEK EFFICACY RESULTS OF THE NORD-STAR TRIAL

Background:

The optimal first-line treatment of patients (pts) with early rheumatoid arthritis (RA) is yet to be established.

Objectives:

The primary aim was to assess and compare the proportion of pts who achieved remission with active conventional therapy (ACT) and with three different biologic therapies after 24 wks. Secondary aims were to assess and compare other efficacy measures.

Methods:

The investigator-initiated NORD-STAR trial (NCT01491815) was conducted in the Nordic countries and Netherlands. In this multicenter, randomized, open-label, blinded-assessor study pts with treatment-naïve, early RA with DAS28>3.2, and positive RF or ACPA, or CRP >10mg/L were randomized 1:1:1:1. Methotrexate (25 mg/week after one month) was combined with: 1) (ACT): oral prednisolone (tapered quickly);or: sulphasalazine, hydroxychloroquine and mandatory intra-articular (IA) glucocorticoid (GC) injections in swollen joints <wk 20; 2) certolizumab 200 mg EOW SC (CZP); 3) abatacept 125 mg/wk SC (ABA); tocilizumab 162 mg/wk SC (TCZ). IA GC was allowed in all arms <wk 20. Primary outcome was clinical disease activity index remission (CDAI≤2.8) at wk 24. Secondary outcomes included CDAI remission over time and other remission criteria. Dichotomous outcomes were analyzed by adjusted logistic regression with non-responder imputation (NRI). Non-inferiority analyses had a pre-specified margin of 15%.

Results:

812 pts were randomized. Age was 54.3±14.7 yrs (mean±SD), 31.2% were male, DAS28 5.0±1.1, 74.9% were RF and 81.9% ACPA positive. Fig 1 shows the adjusted CDAI remission rates over time with 95% CI. Table shows crude remission and response rates and absolute differences in adjusted remission and response rates (superiority analysis). Differences in remission and response rates with CZP and TCZ, but not with ABA, remained within the pre-defined non-inferiority margin versus ACT, Fig 2.

Figure 1.

CDAI remission over time (adj. estimates with 95% CI)

Figure 2.

Non-inferiority analysis of protocol population. Estimated differences in CDAI remission rates between Arm 1 (active conventional therapy) and Arms 2, 3, and 4 (biologic arms) as reference with 95% confidence intervals, adjusted for gender, ACPA status, country, age, body-mass index and baseline DAS28-CRP. ABA, abatacept; CZP, certolizumab-pegol; MTX, methotrexate; TCZ, tocilizumab.

Conclusion:

High remission rates were found across all four treatment arms at 24 wks. Higher CDAI remission rate was observed for ABA versus ACT (+9%) and for CZP (+4%), but not for TCZ (-1%). With the predefined 15% margin, ACT was non-inferior to CZP and TCZ, but not to ABA. This underscores the efficacy of active conventional therapy based on MTX combined with glucocorticoids and may guide future treatment strategies for early RA.

Table.

Primary and key secondary outcomes at 24 weeks (ITT)

Active conventional therapy (ACT)Certolizumab+MTXAbatacept+MTXTocilizumab+MTXNo of pts (ITT)200203204188§Crude remission and response ratesCDAI remission42.0%47.8%52.5%41.0%ACR/EULAR Boolean remission34.0%38.4%37.3%31.4%DAS28 remission63.5%68.5%69.6%63.3%SDAI remission41.5%49.8%51.5%42.6%EULAR good response71.5%76.9%79.9%71.3%Difference (95% CI) in rates with Arm 1 as reference (adjusted)CDAI remissionRef4% (-5 to 13%)9% (0.1 to 19%)-1% (-10 to 9%)ACR/EULAR Boolean remissionRef4% (-6 to 13%)5% (-5 to 14%)-4% (-13 to 6%)DAS28 remissionRef3% (-6 to 11%)5% (-4 to 13%)-1% (-10 to 8%)SDAI remissionRef6% (-3 to 18%)9% (-0.3 to 18%)1% (-8 to 11%)EULAR good responseRef4% (-4 to 14%)8% (-2 to 18%)0.4% (-10 to 11%)

§17 patients allocated to Tocilizumab did not receive it due to its unavailability and were excluded from ITT.

Acknowledgments:

Manufacturers provided CZP and ABA.

Disclosure of Interests:

Merete L. Hetland Grant/research support from: BMS, MSD, AbbVie, Roche, Novartis, Biogen and Pfizer, Consultant of: Eli Lilly, Speakers bureau: Orion Pharma, Biogen, Pfizer, CellTrion, Merck and Samsung Bioepis, Espen A Haavardsholm Grant/research support from: AbbVie, UCB Pharma, Pfizer Inc, MSD Norway, Roche Norway, Consultant of: Pfizer, AbbVie, Janssen-Cilag, Gilead, UCB Pharma, Celgene, Lilly, Paid instructor for: UCB Pharma, Speakers bureau: Pfizer, AbbVie, UCB Pharma, Celgene, Lilly, Roche, MSD, Anna Rudin Consultant of: Astra/Zeneca, Dan Nordström Consultant of: Abbvie, Celgene, Lilly, Novartis, Pfizer, Roche and UCB., Speakers bureau: Abbvie, Celgene, Lilly, Novartis, Pfizer, Roche and UCB., Michael Nurmohamed Grant/research support from: Not related to this research, Consultant of: Not related to this research, Speakers bureau: Not related to this research, Björn Gudbjornsson Speakers bureau: Novartis and Amgen, Jon Lampa Speakers bureau: Pfizer, Janssen, Novartis, Kim Hørslev-Petersen: None declared, Till Uhlig Consultant of: Lilly, Pfizer, Speakers bureau: Grünenthal, Novartis, Gerdur Gröndal: None declared, Mikkel Ǿstergaard Grant/research support from: AbbVie, Bristol-Myers Squibb, Celgene, Merck, and Novartis, Consultant of: AbbVie, Bristol-Myers Squibb, Boehringer Ingelheim, Celgene, Eli Lilly, Hospira, Janssen, Merck, Novartis, Novo Nordisk, Orion, Pfizer, Regeneron, Roche, Sandoz, Sanofi, and UCB, Speakers bureau: AbbVie, Bristol-Myers Squibb, Boehringer Ingelheim, Celgene, Eli Lilly, Hospira, Janssen, Merck, Novartis, Novo Nordisk, Orion, Pfizer, Regeneron, Roche, Sandoz, Sanofi, and UCB, Marte Heiberg: None declared, Jos Twisk: None declared, Simon Krabbe: None declared, Kristina Lend: None declared, Inge Olsen: None declared, Joakim Lindqvist: None declared, Anna-Karin H Ekwall Consultant of: AbbVie, Pfizer, Kathrine L. Grøn Grant/research support from: BMS, Meliha C Kapetanovic: None declared, Francesca Faustini: None declared, Riitta Tuompo: None declared, Tove Lorenzen: None declared, Giovanni Cagnotto: None declared, Eva Baecklund: None declared, Oliver Hendricks Grant/research support from: Pfizer, MSD, Daisy Vedder: None declared, Tuulikki Sokka-Isler: None declared, Tomas Husmark: None declared, Maud-Kristine A Ljosa: None declared, Eli Brodin: None declared, Torkell Ellingsen: None declared, Annika Soderbergh: None declared, Milad Rizk Speakers bureau: AbbVie, Åsa Reckner: None declared, Per Larsson: None declared, Line Uhrenholt Speakers bureau: Abbvie, Eli Lilly and Novartis (not related to the submitted work), Søren Andreas Just: None declared, David Stevens: None declared, Trine Bay Laurberg Consultant of: UCB Pharma (Advisory Board), Gunnstein Bakland Consultant of: Novartis, UCB, Ronald van Vollenhoven Grant/research support from: BMS, GSK, Lilly, UCB, Pfizer, Roche, Consultant of: AbbVie, AstraZeneca, Biogen, Biotest, Celgene, Gilead, Janssen, Pfizer, Servier, UCB, Speakers bureau: AbbVie, Pfizer, UCB

Predicting return to work among patients with colorectal cancer

BACKGROUND

The increase in prevalence of colorectal cancer among young patients coupled with an older retirement age in developed countries means that more patients are being diagnosed with colorectal cancer while still at work. The aim of this study was to develop prediction models for return to work by 1 and 2 years after the start of sick leave.

METHODS

This was a retrospective registry-based cohort study of data from a nationwide occupational health service in the Netherlands. Only employed patients with colonic or rectal cancer treated with curative intent were included. Two predictor variable models were developed using multivariable logistic regression with backward selection. Calibration, discrimination and explained variance were used to assess model performance, and internal validation by bootstrapping was performed.

RESULTS

Median time to return to work for 317 included patients was 423 (95 per cent c.i. 379 to 467) days. Two-thirds of patients had returned to work by 2 years after the start of the sick leave. Presence of metastases, adjuvant treatment, stoma, emotional distress and postoperative complications were predictors of not returning to work in the 1-year model. In the 2-year model, presence of metastases, emotional distress, postoperative complications, company size and the trajectory of the return-to-work process were predictors.

CONCLUSION

Almost 70 per cent of patients with colorectal cancer in this population returned to work within 2 years after the start of sick leave. The models can be used to guide patients early in colorectal cancer treatment about the likelihood of returning to work, and to identify and modify barriers that could facilitate this.

Employees' Perceptions of Social Norms as a Result of Implementing the Participatory Approach at Supervisor Level: Results of a Randomized Controlled Trial

Purpose A multifaceted implementation strategy was targeted at supervisors to encourage them to apply a participatory approach (PA) in dealing with employees' work functioning problems due to health concerns. This paper assesses the effect on employees' perceived social norms regarding the use of the PA to deal with work functioning problems. Methods Three organizations participated in a cluster randomized controlled trial, with randomization at the department level. Supervisors in the PA intervention departments received the implementation strategy consisting of a working group meeting, supervisor training, and optional coaching. Supervisors in the control departments received written information about the PA only. In two of the organizations, employees were invited to complete surveys at baseline and at 6-month follow-up. The primary outcome was perceived social norms regarding the use of the PA to deal with work functioning problems. Secondary measures included attitudes and self-efficacy, and intention regarding joint problem solving, and sick leave data. Effects were analyzed using multilevel analyses to account for nesting of cases. Results At baseline, 273 employees participated in the survey, with follow-up analyses of 174 employees. There were no statistically significant group effects on employee outcome measures. The intervention group showed a larger reduction in mean sick days (from 4.6 to 2.4 days) versus the control group (from 3.8 to 3.6 days), but this difference did not reach statistical significance (p > .05). Conclusion The multifaceted strategy to implement the participatory approach for supervisors did not show effects on outcomes at the employee level. To gain significant effects at the employee level, may require that an implementation strategy not only targets management and supervisors, but also employees themselves.

TRIAL REGISTRATION

NTR3733.

A lifestyle intervention improves fatigue, mental health and social support among adolescents and young adults with cerebral palsy: focus on mediating effects

Objective:

To evaluate the effect of a lifestyle intervention on fatigue, participation, quality of life, gross motor functioning, motivation, self-efficacy and social support, and to explore mediating effects of physical behavior and physical fitness.

Design:

A randomized controlled trial with intention to treat analysis.

Setting:

Rehabilitation centers in university hospitals in the Netherlands.

Subjects:

Adolescents and young adults with spastic cerebral palsy.

Interventions:

A six-month lifestyle intervention that consisted of physical fitness training combined with counseling sessions focused on physical behavior and sports participation.

Main measures:

Fatigue, social participation, quality of life and gross motor functioning.

Results:

The lifestyle intervention was effective in decreasing fatigue severity during the intervention (difference = –6.72, p = 0.02) and in increasing health-related quality of life with respect to bodily pain (difference = 15.14, p = 0.01) and mental health (difference = 8.80, p = 0.03) during follow-up. Furthermore, the domain participation and involvement of the social support increased during both the intervention (difference = 5.38, p = 0.04) and follow-up (difference = 4.52, p = 0.03) period. Physical behavior or physical fitness explained the observed effects for 22.6%, 9.7% and 28.1% of improvements on fatigue, bodily pain and mental health, but had little effect on social support (2.6%).

Interpretation:

Fatigue, bodily pain, mental health and social support can be improved using a lifestyle intervention among adolescents and young adults with cerebral palsy. Furthermore, substantial mediating effects were found for physical behavior and physical fitness on fatigue, bodily pain and mental health.

Efficacy and long-term safety of alipogene tiparvovec (AAV1-LPLS447X) gene therapy for lipoprotein lipase deficiency: an open-label trial

We describe the 2-year follow-up of an open-label trial (CT-AMT-011-01) of AAV1-LPL(S447X) gene therapy for lipoprotein lipase (LPL) deficiency (LPLD), an orphan disease associated with chylomicronemia, severe hypertriglyceridemia, metabolic complications and potentially life-threatening pancreatitis. The LPL(S447X) gene variant, in an adeno-associated viral vector of serotype 1 (alipogene tiparvovec), was administered to 14 adult LPLD patients with a prior history of pancreatitis. Primary objectives were to assess the long-term safety of alipogene tiparvovec and achieve a ≥40% reduction in fasting median plasma triglyceride (TG) at 3-12 weeks compared with baseline. Cohorts 1 (n=2) and 2 (n=4) received 3 × 10(11) gc kg(-1), and cohort 3 (n=8) received 1 × 10(12) gc kg(-1). Cohorts 2 and 3 also received immunosuppressants from the time of alipogene tiparvovec administration and continued for 12 weeks. Alipogene tiparvovec was well tolerated, without emerging safety concerns for 2 years. Half of the patients demonstrated a ≥40% reduction in fasting TG between 3 and 12 weeks. TG subsequently returned to baseline, although sustained LPL(S447X) expression and long-term changes in TG-rich lipoprotein characteristics were noted independently of the effect on fasting plasma TG.

Type 2 diabetes mellitus as a risk factor for the onset of depression: a systematic review and meta-analysis

AIMS/HYPOTHESIS

An earlier meta-analysis showed that diabetes is a risk factor for the development and/or recurrence of depression. Yet whether this risk is different for studies using questionnaires than for those relying on diagnostic criteria for depression has not been examined. This study examined the association of diabetes and the onset of depression by reviewing the literature and conducting a meta-analysis of longitudinal studies on this topic.

METHODS

EMBASE, MEDLINE and PsycInfo were searched for articles published up to September 2009. All studies that examined the relationship between type 2 diabetes and the onset of depression were included. Pooled relative risks were calculated using fixed and random effects models.

RESULTS

Eleven studies met our inclusion criteria for this meta-analysis. Based on the pooled data, including 48,808 cases of type 2 diabetes without depression at baseline, the pooled relative risk was 1.24 (95% CI 1.09-1.40) for the random effects model. This risk was significantly higher for studies relying on diagnostic criteria of depression than for studies using questionnaires. However, this difference was no longer significant when controlled for year of publication.

CONCLUSIONS/INTERPRETATION

Compared with non-diabetic controls, people with type 2 diabetes have a 24% increased risk of developing depression. The mechanisms underlying this relationship are still unclear and warrant further research.

Cellular tropism and transduction properties of seven adeno-associated viral vector serotypes in adult retina after intravitreal injection

Recombinant adeno-associated virus (rAAV) vectors are increasingly being used as tools for gene therapy, and clinical trials have begun in patients with genetically linked retinal disorders. Intravitreal injection is optimal for the transduction of retinal ganglion cells (RGCs), although complete selectivity has not been achieved. There may also be advantages in using intravitreal approaches for the transduction of photoreceptors. Here we compared the cellular tropism and transduction efficiency of rAAV2/1, -2/2, -2/3, -2/4, -2/5, -2/6 and -2/8 in adult rat retina after intravitreal injection. Each vector encoded green fluorescent protein (GFP), and the number, laminar distribution and morphology of transduced GFP(+) cells were determined using fluorescent microscopy. Assessment of transduced cell phenotype was based on cell morphology and immunohistochemistry. rAAV2/2 and rAAV2/6 transduced the greatest number of cells, whereas rAAV2/5 and rAAV2/8 were least efficient. Most vectors primarily transduced RGCs; however, rAAV2/6 had a more diverse tropism profile, with 46% identified as amacrine or bipolar cells, 23% as RGCs and 22% as Müller cells. Müller cells were also frequently transduced by rAAV2/4. The highest photoreceptor transduction was seen after intravitreal rAAV2/3 injection. These data facilitate the design and selection of rAAV vectors to target specific retinal cells, potentially leading to an improved gene therapy for various human retinal pathologies.

[Evaluation of a programme for the prenatal screening for Down's syndrome by ultrasonographic nuchal translucency measurement and serum determinations in the first trimester of pregnancy]

OBJECTIVE

To determine the diagnostic value of the combination screening test for Down's syndrome in women in the first trimester of pregnancy.

DESIGN

Secondary data analysis.

METHOD

The data from 2026 consecutive combination tests that were carried out in the period 1 May 2001-31 October 2003 in the VU Medical Centre in Amsterdam, The Netherlands, were analysed. The combination test comprised ultrasonographic neck fold measurement together with determination of the serum levels of free human beta-chorionic gonadotrophin and pregnancy-associated plasma protein A. The chance of Down's syndrome in the foetus was calculated using the median values of the Fetal Medicine Foundation (FMF) and medians based on the population in the VU Medical Centre. A chance > or = 1:200 was considered elevated. Follow-up data were collected from the medical records and from patient reports.

RESULTS

The data from 25 patients were excluded because of incompleteness of the investigation or the presence of diabetes mellitus in the pregnant subject. Follow-up data were obtained from 1759 of the 2001 remaining women (88%). Of the 1759 women, 49% were < or = 35 years old and 51% were > or = 36 years of age. Down's syndrome was diagnosed in 21 pregnancies, 16 of which were in the advanced maternal age group of patients. The detection percentage of Down's syndrome by nuchal translucency measurement was 67 with 3 false-positives when calculated on the basis of the FMF-medians and 76 with 6 false-positives when calculated on the basis of the VU Medical Centre medians. With the combination test, the detection percentage of Down's syndrome was 86 with 11 false-positives when calculated on the basis of the FMF-medians and 90 with 5 false-positives when calculated on the basis of the VU Medical Centre medians.

CONCLUSION

The diagnostic value of the first-trimester combination test was greater than that of only nuchal translucency measurement. Moreover, the diagnostic value was greater if the chances were calculated on the basis of the median values of the VU Medial Centre population than when other median values were used.

Identifying predictors of comfort and discomfort in using hand tools

The aim of the study was to identify predictors of comfort and discomfort in using hand tools. For this purpose, the comfort questionnaire for hand tools (CQH) was developed based on the results of a previous study. In the current study, four screwdrivers were evaluated on comfort (expected comfort at first sight and comfort after short time use) using the CQH and discomfort (local perceived discomfort). The results showed that expected comfort at first sight was predicted by aesthetics. Additionally, functionality and physical interaction, and adverse body effects were the major predictors of overall comfort after short time use. Discomfort was predicted by adverse body effects only. It is concluded that comfort and discomfort in using hand tools have partly the same underlying factors: discomfort feelings also affect the comfort experience.

Increased nuchal translucency and distended jugular lymphatic sacs on first-trimester ultrasound

OBJECTIVE

To investigate the presence and volume of jugular lymphatic sacs (JLS) in first-trimester fetuses with normal nuchal translucency thickness (NT) and in those with increased NT.

METHODS

This was a prospective study of 26 fetuses with NT > 95(th) percentile, which were compared with 137 fetuses with normal NT. Following crown-rump length (CRL) and NT measurement the neck region of the fetus was studied by transvaginal ultrasound. The JLS presented as spheroidal translusencies in the anterolateral region of the neck.

RESULTS

The prevalence of JLS differed significantly between fetuses with enlarged NT and the control group (P < 0.0001). In the group of 26 fetuses with increased NT, 22 had clearly visible JLS. Chorionic villus sampling revealed aneuploidy in 10 and euploidy in 16 fetuses. In the control group two fetuses, with NT values of 2.8 mm and 2.9 mm, had JLS; pregnancy outcome was normal in both cases. Logistic regression analysis in the total study group showed that an increase in NT was associated with a greater probability of JLS being present (for NT = 3-3.5 mm, probability = 0.67; for NT > 3.5 mm, probability = 0.93). In fetuses with JLS, an increase in CRL was associated with a significant increase in right JLS volume (r = 0.51; P-value = 0.01) and a non-significant increase in left sac volume (r = 0.40; P-value = 0.09). Increase in NT was not associated with a significant increase in JLS volume.

CONCLUSION

There is a significant association between increased NT and the presence of JLS on first-trimester ultrasound. In our opinion, the pathophysiological explanation for increased NT lies in a disturbance in lymphangiogenesis.

Gene therapy for genetic lipoprotein lipase deficiency: from promise to practice

Lipoprotein lipase (LPL) deficiency is a rare, hereditary disorder of lipoprotein metabolism characterised by severely increased triglyceride levels, and associated with an increased risk for pancreatitis. Since no adequate treatment modality is available for this disorder, we set out to develop an LPL gene therapy protocol. This paper focuses on the clinical presentation of LPL deficiency, summarises the preclinical investigations in animal models and describes the rationale to evaluate gene therapy for this monogenetic disorder of lipid metabolism in humans.

Comparison of E-selectin expression at mRNA and protein levels in murine models of inflammation

BACKGROUND

Drug targeting to activated endothelial cells via E-selectin is currently being explored as a new approach to treat chronic inflammatory disorders. This approach uses E-selectin directed antibodies as carrier molecules to selectively deliver anti-inflammatory drugs into activated endothelial cells, thereby theoretically decreasing drug-associated side-effects. Therapeutic effects of developed drug targeting constructs will have to be tested in animal models of inflammation, in which E-selectin is expressed during the course of the disease. In this study several murine models of inflammation were investigated regarding expression of E-selectin.

METHODS

E-selectin expression was determined both at the mRNA level using RT-PCR and at the protein level by immunohistochemistry using two monoclonal antibodies (10E9.6 and MES-1). The models studied included delayed type hypersensitivity induced skin inflammation, dextran sodium sulphate induced colitis, kidney ischemia/reperfusion injury, atherosclerosis in ApoE knockout mice, and collagen induced arthritis.

RESULTS

In all animal models E-selectin mRNA expression was detected, although to a different extent. In contrast, only the delayed type hypersensitivity model and, to a minor extent, the collagen induced arthritis model showed E-selectin protein expression.

CONCLUSION

These results stress the need to determine E-selectin protein expression and not only mRNA expression, when choosing an animal model for testing E-selectin directed drug targeting preparations. In addition, in the arthritis model, E-selectin protein detection was dependent on the particular anti-E-selectin antibody used. This finding may not only have implications for the development and/or choice of homing devices to be used in E-selectin directed drug targeting preparations, but also for inflammation research in general.

Quality of care for patients with Type 2 diabetes mellitus--a long-term comparison of two quality improvement programmes in the Netherlands

AIM

To compare two intervention programmes, aimed at improving the quality of care provided for patients with Type 2 diabetes in the longer term.

METHODS

A retrospective comparison of data derived from two non-randomized trials with 3.5 years of follow-up. In the first intervention group 401 patients were included, 413 in the second intervention group and 105 in the reference group. The first programme focused on improving the skills and knowledge of general practitioners (GPs) with regard to Type 2 diabetes, and supported them in making organizational changes in their practice (GP care only). Centralized shared diabetes care was implemented in the second programme in which the GPs received therapy advice according to a protocol for each individual patient. The patients were also encouraged in self-management, and received structured diabetes education (Diabetes Service). The main patient outcomes were HbA1c, blood pressure and serum lipid levels. Multilevel analysis was applied to adjust for dependency between repeated observations within one patient and for clustering of patients within general practices.

RESULTS

The HbA1c levels of patients of GPs who were supported by the Diabetes Service improved significantly more than the HbA1c levels of patients receiving GP care only (-0.28% [95% confidence interval (CI) -0.45; -0.11]). In contrast, the systolic blood pressure of patients receiving GP care only decreased more than that of patients of GPs supported by the Diabetes Service [4.14 mmHg (95% CI 1.77, 6.51)].

CONCLUSION

A Diabetes Service, providing GPs with individual therapy advice and patient education, resulted in better glycaemic control over 3.5 years than an intervention aimed at improving the skills of GPs in combination with organizational changes in the general practice.

Effectiveness of a measurement feedback system on outcome in rheumatoid arthritis: a controlled clinical trial

BACKGROUND

With the help of a measurement feedback system, the treatment strategy for individual patients with rheumatoid arthritis (RA) can be adjusted to achieve optimal control of disease activity.

OBJECTIVE

To study whether a measurement feedback system is effective in reducing disease activity in patients with RA.

METHODS

Forty eight rheumatologists and 264 patients participated in a controlled clinical trial. A three month control period was followed by a 12 month period, where feedback on disease activity, disability, and damage was provided to the rheumatologist. The primary outcome measure was the rheumatoid arthritis disease activity index (RADAI).

RESULTS

The feedback system was used for 142/228 (62%) patients. Disease modifying antirheumatic drug changes occurred in 69/169 (41%) patients. In patients with high disease activity and feedback use (n=70), the RADAI decreased in the feedback period by -0.27 points per 30 days (p<0.05), as compared with the control period. Patients for whom the feedback system was used had a better outcome than non-users.

CONCLUSION

Much more training on the use of a feedback system and outcome measures, as well as the inclusion of explicit treatment guidelines will be necessary to increase the clinical use of measurement feedback and, possibly, to reduce disease activity for a larger number of patients with RA.

Associations between physical fitness and activity patterns during adolescence and cardiovascular risk factors in young adulthood: the Northern Ireland Young Hearts Project

The aim of the present study was to examine relationships between cardiovascular disease (CVD) risk factor status in young adulthood (mean age = 22.5 yrs) and antecedent physical fitness and physical activity at ages 12 and 15 years. The data were obtained from the Young Hearts Project, a longitudinal observational study of CVD risk factors in a representative sample of young people from Northern Ireland. Physical fitness was measured by the 20-metre endurance shuttle run, and physical activity and sports participation by a self-report recall questionnaire. CVD risk factors examined included serum total cholesterol (TC) and HDL cholesterol concentrations, the TC:HDL ratio, systolic and diastolic blood pressure and body fatness (sum of four skinfolds). Linear regression analyses showed modest relationships between physical fitness in adolescence and both TC:HDL ratio and body fatness in young adulthood. No such relationships were apparent for adolescent physical activity. The promotion of physical fitness during adolescence may reduce exposure to other risk factors lasting into early adulthood.

Relationship between physical activity and bone mineral status in young adults: the Northern Ireland Young Hearts Project

Physical activity during the first three decades of life may increase peak bone mass and reduce future osteoporosis risk. The aim of this study was to determine the extent to which different components of physical activity may influence bone mineral status within a representative population sample of young men and women. Bone mineral density (BMD) and content (BMC) were determined at the lumbar spine and femoral neck in 242 men and 212 women, aged 20-25 years, by dual-energy X-ray absorptiometry. Physical activity was assessed by a self-report questionnaire designed to measure the frequency and duration of physical activity and its components (i.e., work, non-sports leisure, sports-related activities, and peak strain sports activities). Potential confounding factors such as height, weight, diet, and smoking habits were also assessed. In multivariate linear regression models, sports activity and peak strain sports activity undertaken by men were strongly associated with both lumbar spine BMD (beta = 0.35 [0.21, 0.49] and beta = 0.31 [0.17, 0.44], respectively) and BMC (beta = 0.33 [0.21, 0.45] and beta = 0.26 [0.14, 0.38], respectively) and femoral neck BMD (beta = 0.35 [0.21, 0.48] and beta = 0.27 [0.14, 0.40], respectively) and BMC (beta = 0.32 [0.19, 0.44] and beta = 0.29 [0.17, 0.41], respectively) (all p < 0.01), but work and non-sports leisure activities were not. In women, there were no associations between bone measurements and any component of physical activity. In models involving all subjects the gender/sports activity, but not the gender/peak strain, interaction term was statistically significant. Sports activity explained 10.4% of the observed variance in lumbar spine BMD in men, but <1% in women. These results demonstrate the importance of sports activities, especially those involving high peak strain, in determining peak bone status in young men. Failure to observe this association in women reflects their lower participation in such activities, but they may have the same capacity to benefit from these activities as men. Intervention studies are warranted to determine whether peak bone density in women can be improved by participating, during childhood and adolescence, in sports activities involving high peak strain.

The effect of nutrient intake on bone mineral status in young adults: the Northern Ireland young hearts project

Optimizing peak bone mass in early life may reduce osteoporosis risk in later life. Such optimization may be partly dependent upon diet. In the present study, nutrient intakes and selected lifestyle parameters were assessed in adolescent subjects (238 males, 205 females; aged 15 y) and again, in the same subjects, on one occasion in young adulthood (aged between 20 and 25 y). The extent of the relationships between these parameters and bone mineral density (BMD), dual energy X-ray absorptiometry (DXA), lumbar spine (L2-L4), and femoral neck measured concurrently with diet in young adulthood only, was assessed. Adjusted linear regression models were constructed. Variables included a measure of pubertal status (at age 15 y), age (at young adulthood), height, weight, physical activity, smoking, and mean daily intakes of energy, calcium, protein, vitamin D, phosphorus, total fat, and alcohol. In both sexes, body weight at adolescence and young adulthood was the only factor consistently positively associated with BMD at both measurement sites. Effects of nutrient intake on BMD were inconsistent. Vitamin D and calcium intakes reported by female adolescents showed significant positive relationships with BMD measured in young adulthood (vitamin D measured at the lumbar spine; calcium measured at the femoral neck). The positive relationship between vitamin D and BMD remained significant at young adulthood, but at the femoral neck rather than at the lumbar spine. Also in females, intakes of phosphorus and the calcium:phosphorus ratio (Ca:P) at adolescence were strongly negatively related to femoral neck BMD measured at young adulthood. In males, however, Ca:P reported at young adulthood had a significant positive relationship with lumbar spine BMD, whereas Ca:protein was negatively associated with BMD at the lumbar spine. Intakes of Ca reported by adolescent males also had a strong negative effect on lumbar spine BMD measured at young adulthood.

Fitness, fatness, and coronary heart disease risk in adolescents: the Northern Ireland Young Hearts Project

PURPOSE

The purpose of this study was to examine the independence and relative strengths of association between coronary heart disease (CHD) risk status and both body fatness and cardiorespiratory (C-R) fitness in 12- and 15-yr-old adolescents.

METHODS

The study cohort consisted of 1015 schoolchildren aged 12 and 15 yr (251 12-yr-old boys, 258 12-yr-old girls, 252 15-yr-old boys, and 254 15-yr-old girls), representing a 2% random sample of each population group. For each child, height, weight, sexual maturity (pubertal status), skin-fold thicknesses (4 sites), blood pressure (random zero sphygmomanometer), nonfasting serum total, and high density lipoprotein (HDL)-cholesterol and C-R fitness (20-m shuttle run; 20-MST) were determined under standardized conditions. Socioeconomic status and habitual physical activity were also determined from questionnaire information. Multiple regression analyses were carried out to examine relationships between five CHD risk factors, and fitness and fatness and to examine the relative strengths of fitness and fatness on CHD risk status, correcting for potential confounding variables.

RESULTS

Our main findings were: 1) Relationships between fatness and CHD risk factors are invariably stronger than between fitness and the same risk factors. For example, partially adjusted standardized regression coefficients for 12-yr-old boys revealed significant relationships between all five CHD risk factors and fatness, compared with three of five for fitness. The corresponding figures for 12-yr-old girls were three of five (fatness) and one of five (fitness). Broadly similar results were apparent for 15-yr-olds. 2) Although relationships between fitness and CHD risk factors do not survive further adjustment for fatness, the relationships between fatness and CHD risk are more robust and are unaffected by further adjustment for fitness.

CONCLUSION

Our results indicate that the observed relationships between C-R fitness and CHD risk status in adolescents are mediated by fatness, whereas the observed relationships with fatness are independent of fitness. Primary prevention of CHD during childhood should therefore concentrate upon preventing or reversing undue weight gain.

The role of the LDL receptor in apolipoprotein B secretion

Familial hypercholesterolemia is caused by mutations in the LDL receptor gene (Ldlr). Elevated plasma LDL levels result from slower LDL catabolism and a paradoxical lipoprotein overproduction. We explored the relationship between the presence of the LDL receptor and lipoprotein secretion in hepatocytes from both wild-type and LDL receptor-deficient mice. Ldlr(-/-) hepatocytes secreted apoB100 at a 3.5-fold higher rate than did wild-type hepatocytes. ApoB mRNA abundance, initial apoB synthetic rate, and abundance of the microsomal triglyceride transfer protein 97-kDa subunit did not differ between wild-type and Ldlr(-/-) cells. Pulse-chase analysis and multicompartmental modeling revealed that in wild-type hepatocytes, approximately 55% of newly synthesized apoB100 was degraded. However, in Ldlr(-/-) cells, less than 20% of apoB was degraded. In wild-type hepatocytes, approximately equal amounts of LDL receptor-dependent apoB100 degradation occured via reuptake and presecretory mechanisms. Adenovirus-mediated overexpression of the LDL receptor in Ldlr(-/-) cells resulted in degradation of approximately 90% of newly synthesized apoB100. These studies show that the LDL receptor alters the proportion of apoB that escapes co- or post-translational presecretory degradation and mediates the reuptake of newly secreted apoB-containing lipoprotein particles.

Development of muscle strength in relation to training level and testosterone in young male soccer players

Isometric and functional strength of ninety-eight 11-yr-old male soccer players at an elite (E) and nonelite (NE) level were determined (3-4 times) through a 2-yr period, and the changes were related to growth and maturation. The initial isometric strength for extension with dominant leg [1,502 +/- 35 (E) vs. 1,309 +/- 39 (NE) N], extension with nondominant leg (1,438 +/- 37 vs. 1,267 +/- 45 N), extension with both legs (2,113 +/- 76 vs. 1,915 +/- 72 N), back muscles (487 +/- 11 vs. 414 +/- 10 N), abdominal muscles (320 +/- 9 vs. 294 +/- 8 N), and handgrip (304 +/- 10 vs. 259 +/- 8 N) increased by 15-40% during the period. Broad jump increased (P < 0. 05) by 15 (E) and 10% (NE). The E players had higher (P < 0.05) initial isometric strength and broad jump performance compared with NE players, and differences were maintained throughout the period (multiple ANOVA for repeated measures) also when adjustment was made for age, dimensions, testosterone, and insulin-like growth factor I (generalized estimating equations analyses). The development of strength for both E and NE players together was significantly (P < 0. 001) related to changes in serum testosterone concentrations. The present data indicate that testosterone is important for development of strength in young boys and that, independent of serum testosterone concentration, E players have developed greater muscle strength compared with NE players.

Lipoprotein cholesterol uptake mediates up-regulation of bile-acid synthesis by increasing cholesterol 7alpha-hydroxylase but not sterol 27-hydroxylase gene expression in cultured rat hepatocytes

Lipoproteins may supply substrate for the formation of bile acids, and the amount of hepatic cholesterol can regulate bile-acid synthesis and increase cholesterol 7alpha-hydroxylase expression. However, the effect of lipoprotein cholesterol on sterol 27-hydroxylase expression and the role of different lipoproteins in regulating both enzymes are not well established. We studied the effect of different rabbit lipoproteins on cholesterol 7alpha-hydroxylase and sterol 27-hydroxylase in cultured rat hepatocytes. beta-Migrating very-low-density lipoprotein (betaVLDL) and intermediate-density lipoprotein (IDL) caused a significant increase in the intracellular cholesteryl ester content of cells (2. 3- and 2-fold, respectively) at a concentration of 200 microgram of cholesterol/ml, whereas high-density lipoprotein (HDL, 50% v/v), containing no apolipoprotein E (apo E), showed no effect after a 24-h incubation. betaVLDL and IDL increased bile-acid synthesis (1. 9- and 1.6-fold, respectively) by up-regulation of cholesterol 7alpha-hydroxylase activity (1.7- and 1.5-fold, respectively). Dose- and time-dependent changes in cholesterol 7alpha-hydroxylase mRNA levels and gene expression underlie the increase in enzyme activity. Incubation of cells with HDL showed no effect. Sterol 27-hydroxylase gene expression was not affected by any of the lipoproteins added. Transient-expression experiments in hepatocytes, transfected with a promoter-reporter construct containing the proximal 348 nucleotides of the rat cholesterol 7alpha-hydroxylase promoter, showed an enhanced gene transcription (2-fold) with betaVLDL, indicating that a sequence important for a cholesterol-induced transcriptional response is located in this part of the cholesterol 7alpha-hydroxylase gene. The extent of stimulation of cholesterol 7alpha-hydroxylase is associated with the apo E content of the lipoprotein particle, which is important in the uptake of lipoprotein cholesterol. We conclude that physiological concentrations of cholesterol in apo E-containing lipoproteins increase bile-acid synthesis by stimulating cholesterol 7alpha-hydroxylase gene transcription, whereas HDL has no effect and sterol 27-hydroxylase is not affected.

Relationships between the development of biological risk factors for coronary heart disease and lifestyle parameters during adolescence: The Northern Ireland Young Hearts Project

The purpose of this study was to examine relationships between the longitudinal development of biological risk factors for coronary heart disease (CHD) (namely, serum lipids, body fatness, blood pressure and cardiorespiratory fitness) and the development of lifestyles considered to be atherogenic. The study was conducted in a representative sample of adolescents from Northern Ireland, a region of high coronary mortality, and atherogenic aspects of lifestyle such as cigarette smoking, physical inactivity and selected aspects of diet were examined. Repeated measurements were made at 12 and 15 y of age on 229 boys and 230 girls. Longitudinal relations were analysed with generalised estimating equations, and the following longitudinal relations were found: for boys diastolic blood pressure was positively associated with vitamin C intake (P = 0.014), and inversely with energy intake (P = 0.006), and smoking (P = 0.048). Systolic blood pressure was inversely related to physical activity (P = 0.012), and smoking (P = 0.000). Body fatness was also inversely related to smoking (P = 0.006). Total cholesterol (TC) was positively related to physical activity (P = 0.044) and the TC:HDL cholesterol ratio positively to vitamin C intake (P = 0.008). Cardiorespiratory fitness was positively related to physical activity (P = 0.000) and inversely to smoking (P = 0.031). For girls, systolic blood pressure was positively related to vitamin C intake (P = 0.042); HDL cholesterol inversely to carbohydrate intake (P = 0.014), fat intake (P = 0.031), cholesterol intake (P = 0.042) and smoking (P = 0.035) and positively to energy intake (P = 0.035). The TC:HDL cholesterol ratio was inversely related to energy intake (P = 0.038) and finally, cardiorespiratory fitness positively to physical activity (P = 0.001). These results offer additional evidence that changes in lifestyle are associated with changes in biological risk factors in adolescents. Education and intervention at this stage, particularly in relation to cigarette smoking, physical activity and certain aspects of diet appear justified as part of a preventative strategy for CHD.

Mortality update of workers exposed to acrylonitrile in The Netherlands

A retrospective cohort study investigating the cause-specific mortality patterns of 2842 workers occupationally exposed to acrylonitrile for at least 6 months before 1 July 1979 was updated. The comparison group consisted of 3961 workers from a nitrogen fixation plant during the same time interval. Industrial hygiene assessments quantified past exposure to acrylonitrile, the use of personal protective equipment, and exposure to other potential carcinogenic agents. All 6803 workers were followed for mortality until 1 January 1996. The follow-up was almost complete (99.6%), and for 99.3% the cause of death was ascertained. Age distribution, follow-up period, and temporal changes in background mortality rates were adjusted for in calculations of standardized mortality ratios for separate causes of death. Cumulative dose-effect relations were determined for 3 exposure categories and 3 latency periods. The results showed that, although cancer mortality fluctuated slightly, no cancer excess seems related to exposure to acrylonitrile.

Mechanism of the slow induction of apolipoprotein A-I synthesis by retinoids in cynomolgus hepatocytes: involvement of retinoic acid and retinoid X receptors

We showed previously that retinoids stimulate apolipoprotein A-I (apoA-I) synthesis in cultured cynomolgus hepatocytes only after a 24-h lag phase. Here we report on the biochemical background of the slow response, the requirement for high retinoic acid concentrations, and the involvement of different retinoid receptors. The time course of the effect of 10 microM all-trans retinoic acid (at-RA) on apoA-I mRNA levels and protein secretion were comparable, i.e., minor increases were observed after a 24-h incubation and mRNA levels were increased 2.2- and 3.5-fold after 48 h and 72 h, respectively. In contrast, apoA-I gene transcription was already increased (2.6-fold) after a 4-h incubation with 10 microM at-RA. At-RA disappeared rapidly from the cultures: after 2 h of incubation 40% of the added amount was left and after 24 h only 2%. RAR beta mRNA and gene expression were increased after incubation with 10 microM at-RA, whereas RAR alpha and RXR alpha mRNA levels and expression remained unchanged. No transcriptional activity and mRNA for other retinoid receptors were detectable. Both RAR-selective (TTNPB) and RXR-selective (3-methyl-TTNEB) agonists induced apoA-I synthesis at 1 and 10 microM. These results show that i) the slow increase in apoA-I secretion is caused by a slow increase of its mRNA level; ii) the apoA-I gene transcription in cynomolgus hepatocytes is induced rapidly by retinoids; iii) the added at-RA disappeared rapidly from the cultures, explaining the necessity for high initial concentrations; iv) RLR alpha and/or RAR beta and RXR alpha are involved in the activation of apoA-I expression by retinoids.

The association between dietary patterns and cardio vascular disease risk indicators in healthy youngsters: results covering fifteen years of longitudinal development

OBJECTIVE

To examine longitudinal relationships between nutrition and risk indicators for cardio vascular diseases (CVD) during adolescence and young adulthood.

DESIGN

A longitudinal study over fifteen years.

SUBJECTS

98 females and 84 males, from 13 to 27 years.

METHODS

By means of six interviews dietary patterns were determined. Blood samples were analyzed for serum concentration of total cholesterol (TC), and high-density-lipoprotein (HDL), blood pressure, body fat and maximal aerobic power (VO2max) were determined. The longitudinal relations were analyzed with generalized estimation equations (GEE), a statistical technique in which relations at different time-points are tested simultaneously.

RESULTS

Compared to Dutch recommendations six out of seven macro nutrients appear to be unfavorable with respect to CVD. Borderline or high CVD risk values are apparent at 27 y in more than 25% of the subjects with respect to percentage body fat and serum total cholesterol in both sexes. In males 40% or more show borderline hypertension. The 'univariate' longitudinal analyses showed significantly positive relations: (1) between the intake of animal protein, saturated fat (SFA), cholesterol (Cho1) and TC, and HDL; (2) between total energy intake (EN) and systolic blood pressure, and VO2max. Significantly negative associations were found: (1) between EN, poly-unsaturated fat (PUFA) and TC concentrations; (2) between EN and sum of four skinfolds (SSF).

CONCLUSIONS

With increasing age, over a period of 15 y in both sexes the SFA and Cho1 intake relate significantly to the development of a negative CVD risk profile. The intake of PUFA relates positive to a CVD risk profile. The significantly negative relation between EN intake and body fat (SSF) is partly explained by the relation between EN and VO2max.

Physical activity, sports participation, and risk factors in adolescents

The purpose of this study was to analyze the relationships between physical activity (ACT), including sports participation (SP) and antecedent risk factors for coronary heart disease (CHD), in a representative sample of adolescents from Northern Ireland, a region of high coronary mortality. Biological and behavioral risk factors were measured in a random sample of 1015 school children aged 12 and 15 yr. ACT and SP were assessed by self-report questionnaire, and relationships with biological risk factors were analyzed with stepwise multiple linear regression after controlling for potential confounders. Results showed that in 15-yr-old males ACT was beneficially associated with systolic blood pressure (P < 0.05), lipid profile, and cardiorespiratory fitness (both P < 0.01). In 15-yr-old females, SP was associated beneficially with fatness and cardiorespiratory fitness. Odds ratios calculated from logistic regression revealed that for the older children, a relatively small drop (-20%) in ACT (boys) or SP (girls) was significantly related to the probability of exposure to multiple risk factors. Overall, relationships were stronger for males rather than females and for older rather than younger children. This study provides further evidence for beneficial associations between ACT, SP, and CHD risk status in adolescents.

Subject-related risk factors for sports injuries: a 1-yr prospective study in young adults

The purpose of this study was to investigate the importance of subject-related risk factors for sports injuries, taking exposure time into account. At baseline in 182 healthy males and females (27 yr) the following subject-related risk factors were assessed: body mass index (BMI), maximal oxygen uptake (direct treadmill measurement), seven aspects of neuromotor fitness (MOPER fitness test), strength of the hamstring and quadriceps muscles (CYBEX), having sustained a sports injury in the 12 months preceding the baseline measurement ("previous injury"), and 16 psychological and psychosocial factors (measured with 8 standard, valid, and reliable questionnaires). For 1 yr, subjects were asked to make daily entries on a monthly log concerning all sports activities exceeding an intensity of 4 MET and all sustained sport injuries. Completed logs were returned by 139 subjects (75 males and 64 females). Fifty-one injuries were registered in 41 subjects. The overall incidence rate (IR) was 3.7 sports injuries per 1000 h of sports participation (95% confidence interval 2.8-4.9). For various subcategories, the following IR per 1000 h of sports participation were calculated: contact sports IR = 11.0 (95% CI 7.4-16.3); noncontact sports IR = 2.3% (95% CI 1.6-3.3); competition IR = 13.4 (95% CI 8.7-20.6); and training IR = 2.8 (95% CI 1.6-5.1). Data were analyzed by stepwise multiple logistic regression. The following five variables were independent and significant (P < 0.05) predictors of risk in sustaining a sport injury: dominance (odds ratio (OR) = 1.71; 95% CI = 1.44-2.03), vital exhaustion (OR = 1.85; CI = 1.22-2.86), stressful life events (OR = 1.84; 95% CI = 1.10-311); these ORs were calculated for an increase of 10% of the range of obtained scores, starting at minimum value. For total sporting time, the OR was calculated by taking the group with a total sporting time below the median (4050 h) as a reference (OR = 6.87; 95% CI = 2.09-22.55). For previous injury, subjects that had not sustained a sports injury in the 12 months preceding the baseline measurements served as a reference for the calculation of the OR (OR = 9.41; 95% CI = 2.80-31.58). These findings confirm that both exposure time and previous injury are more important predictors of sports injuries than psychological, psychosocial, physiological, and anthropometrical factors.

Structural aspects of bile acids involved in the regulation of cholesterol 7 alpha-hydroxylase and sterol 27-hydroxylase

We have recently reported that coordinate down-regulation of cholesterol 7 alpha-hydroxylase and sterol 27-hydroxylase by bile acids results in suppression of bile acid synthesis in cultured rat hepatocytes [Twisk, J., De Wit, E. & Princen, H. M. G. (1995) Biochem. J. 305, 505-511]. In the current study, we have assessed the effects of a large group of different bile acids, both naturally occurring and synthetic, on these two key enzymes, to elucidate structural features which render bile acids potent as regulators of bile acid synthesis. Addition of 50 microM deoxycholate or cholate, two relatively hydrophobic bile acids, to the culture medium of hepatocytes resulted in strong suppression of cholesterol 7 alpha-hydroxylase (suppression of 75%) and 88%, respectively) and sterol 27-hydroxylase activity (suppression of 76% and 72%, respectively). These effects were also reflected in the mRNA levels and the transcriptional activities of the two enzymes, showing a parallel suppression of both parameters in response to cholate (suppression of 78% and 43% for cholesterol 7 alpha-hydroxylase mRNA and transcription, respectively, and suppression of 76% and 42% for sterol 27-hydroxylase mRNA and transcription, respectively). In contrast, no effects were observed with the two hydrophilic bile acids, beta-muricholate and ursocholate. Transient expression analysis in cultured rat hepatocytes, using a promoter-reporter construct containing the proximal part of the cholesterol 7 alpha-hydroxylase promoter, demonstrated a reduction of transcriptional activity by cholate (reduction of 72%), but not by ursocholate. Assessment of the effects of 27 different bile acids, varying in the number, position and orientation (alpha/beta) of hydroxyl groups on the steroid nucleus of the molecule, on cholesterol 7 alpha-hydroxylase mRNA showed only a moderate correlation with the hydrophobicity index of the bile acid involved (r = 0.61; P < 0.0001). Analysis of the three-dimensional structure of a number of these bile acids suggests that hydroxyl groups situated in close proximity to each other within the molecule, creating a hydrophilic environment, as in the case of cholate, may be a prerequisite for a strong inhibitory potency. Deviation from this situation leads to a markedly lesser effect on suppression of cholesterol 7 alpha-hydroxylase and sterol 27-hydroxylase.

Heterogeneous expression of cholesterol 7 alpha-hydroxylase and sterol 27-hydroxylase genes in the rat liver lobulus

We investigated the lobular localization and molecular level of expression of cholesterol 7 alpha-hydroxylase and sterol 27-hydroxylase, two key enzymes in bile acid synthesis, in isolated periportal and pericentral hepatocytes and by in situ hybridization of rat liver. Enzyme activity, mRNA, and gene transcription of cholesterol 7 alpha-hydroxylase were predominant in pericentral hepatocytes of control rats, being 7.9-, 9.9-, and 4.4-fold higher than in periportal hepatocytes, respectively. Similar localization was found for sterol 27-hydroxylase: 2.9-, 2.5-, and 1.7-fold higher enzyme activity, mRNA, and gene transcription, respectively, was found in pericentral hepatocytes. Interruption of the enterohepatic circulation with colestid resulted in upregulation of these parameters for both enzymes, as a consequence of stimulated gene expression mainly in the periportal zone. In contrast, mRNA levels and gene transcription of 3-hydroxy-3-methylglutaryl CoA reductase showed opposite lobular distribution. Selective periportal expression for the latter was enhanced, but remained local, after colestid treatment. In situ hybridization showed unambiguously that cholesterol 7 alpha-hydroxylase mRNA is localized exclusively in the pericentral zone and that sterol 27-hydroxylase mRNA is expressed preferentially in the pericentral region, though less pronounced. Administration of colestid led to expression of both genes within a larger area of the liver lobulus. In conclusion, we suggest that cholesterol 7 alpha-hydroxylase and sterol 27-hydroxylase are coordinately regulated by the bile acid gradient over the lobulus, resulting in predominant expression in the pericentral zone. Opposite lobular localization of cholesterol and bile acid synthesis provides an alternative view to interregulation of these metabolic pathways.

Insulin suppresses bile acid synthesis in cultured rat hepatocytes by down-regulation of cholesterol 7 alpha-hydroxylase and sterol 27-hydroxylase gene transcription

Evidence from in vivo studies indicates that the bile acid pool and bile acid excretion are increased in humans with diabetes mellitus and in experimental diabetic animals, and that both parameters return to normal levels after administration of insulin. To investigate the biochemical background of these changes, the effects of insulin on bile acid synthesis and cholesterol 7 alpha-hydroxylase and sterol 27-hydroxylase, two key enzymes in routing of cholesterol toward bile acids, were studied in cultured rat hepatocytes. Mass production of bile acids was dose dependently diminished, showing significant reduction (-33% to -53%) at physiological concentrations of the hormone (1.4 to 14 nmol/L) and a maximal decrease at 140 nmol/L (-65%). The decrease of bile acid synthesis correlated well with the suppression of cholesterol 7 alpha-hydroxylase and sterol 27-hydroxylase activity. The enzyme activity for cholesterol 7 alpha-hydroxylase, examined in more detail, was dose dependently diminished on incubation of hepatocytes with various concentrations of insulin, reaching maximal reduction at 14 nmol/L of insulin. Maximal decrease of the enzyme activity was seen after 8 hours of incubation (-70%). Insulin strongly reduced the rise in cholesterol 7 alpha-hydroxylase activity induced by incubation with dexamethasone. Sterol 27-hydroxylase activity was inhibited up to -58% after 24 hours of incubation with 140 nmol/L insulin. To study the mechanism of suppression of cholesterol 7 alpha-hydroxylase and sterol 27-hydroxylase activity, the effects of insulin on their respective levels of messenger RNA (mRNA) and gene transcription were assessed. The decrease in enzyme activities could be explained by a concomitant reduction in the cholesterol 7 alpha-hydroxylase (-76%) and sterol 27-hydroxylase (-62%) mRNA level. Transcriptional activity, as assessed by nuclear runoff assays, was decreased to the same extent, i.e., -60% for cholesterol 7 alpha-hydroxylase and -75% for sterol 27-hydroxylase. Transient expression experiments using a construct containing the proximal 348 basepairs of the cholesterol 7 alpha-hydroxylase promoter fused to the chloramphenicol acetyltransferase (CAT) gene (-348Rcat) showed a significant reduction of transcriptional activity (-64%) with insulin, indicating that a sequence important for an insulin-induced transcriptional response is located within the first 348 basepairs, preceding the transcription start of the cholesterol 7 alpha-hydroxylase promoter.(ABSTRACT TRUNCATED AT 400 WORDS)

Suppression of sterol 27-hydroxylase mRNA and transcriptional activity by bile acids in cultured rat hepatocytes

In previous work we have demonstrated suppression of cholesterol 7 alpha-hydroxylase by bile acids at the level of mRNA and transcription, resulting in a similar decline in bile acid synthesis in cultured rat hepatocytes [Twisk, Lehmann and Princen (1993) Biochem. J. 290, 685-691]. In view of the substantial contribution of the 'alternative' or '27-hydroxylase' route to total bile acid synthesis, as demonstrated in cultured rat hepatocytes and in vivo in humans, we here evaluate the effects of various bile acids commonly found in bile of rats on the regulation of sterol 27-hydroxylase in cultured rat hepatocytes. Addition of taurocholic acid, the predominant bile acid in rat bile, to the culture medium of rat hepatocytes resulted in a 72% inhibition of sterol 27-hydroxylase activity. The effect was exerted at the level of sterol 27-hydroxylase mRNA, showing a time- and dose-dependent decline with a maximal suppression (-75%) at 50 microM taurocholic acid after 24 h of culture. The decline in mRNA followed first-order kinetics with an apparent half-life of 13 h. Under these conditions cholesterol 7 alpha-hydroxylase mRNA (-91%) and bile acid synthesis (i.e. chenodeoxycholic and beta-muricholic acid, -81%) were also maximally suppressed. In contrast, no change was found in the level of lithocholic acid 6 beta-hydroxylase mRNA. Assessment of the transcriptional activity of a number of genes involved in routing of cholesterol towards bile acids showed similar suppressive effects of taurocholate on expression of the sterol 27-hydroxylase and cholesterol 7 alpha-hydroxylase genes (-43% and -42% respectively), whereas expression of the lithocholic 6 beta-hydroxylase gene was not affected. Taurocholic acid and unconjugated cholic acid were equally as effective in suppressing sterol 27-hydroxylase mRNA. The more hydrophobic bile acids, chenodeoxycholic acid and deoxycholic acid, also produced a strong inhibition of 57% and 76% respectively, whereas the hydrophilic beta-muricholic acid was not active. We conclude that (1) a number of bile acids, at physiological concentrations, suppress sterol 27-hydroxylase by down-regulation of sterol 27-hydroxylase mRNA and transcriptional activity and (2) co-ordinated suppression of both sterol 27-hydroxylase and cholesterol 7 alpha-hydroxylase results in inhibition of bile acid synthesis in cultured rat hepatocytes.