Gene-Environment Interaction in Parkinson's Disease: Coffee, ADORA2A, and CYP1A2

BACKGROUND AND PURPOSE

Drinking caffeinated coffee has been reported to provide protection against Parkinson's disease (PD). Caffeine is an adenosine A2A receptor (encoded by the gene ADORA2A) antagonist that increases dopaminergic neurotransmission and Cytochrome P450 1A2 (gene: CYP1A2) metabolizes caffeine; thus, gene polymorphisms in ADORA2A and CYP1A2 may influence the effect coffee consumption has on PD risk.

METHODS

In a population-based case-control study (PASIDA) in Denmark (1,556 PD patients and 1,606 birth year- and gender-matched controls), we assessed interactions between lifetime coffee consumption and 3 polymorphisms in ADORA2A and CYP1A2 for all subjects, and incident and prevalent PD cases separately using logistic regression models. We also conducted a meta-analysis combining our results with those from previous studies.

RESULTS

We estimated statistically significant interactions for ADORA2A rs5760423 and heavy vs. light coffee consumption in incident (OR interaction = 0.66 [95% CI 0.46-0.94], p = 0.02) but not prevalent PD. We did not observe interactions for CYP1A2 rs762551 and rs2472304 in incident or prevalent PD. In meta-analyses, PD associations with daily coffee consumption were strongest among carriers of variant alleles in both ADORA2A and CYP1A2.

CONCLUSION

We corroborated results from a previous report that described interactions between ADORA2A and CYP1A2 polymorphisms and coffee consumption. Our results also suggest that survivor bias may affect results of studies that enroll prevalent PD cases.

Lifestyle, family history, and risk of idiopathic Parkinson disease: a large Danish case-control study

The relationship between Parkinson disease (PD) and smoking has been examined in several studies, but little is known about smoking in conjunction with other behaviors and a family history of PD. Using unconditional logistic regression analysis, we studied individual and joint associations of these factors with idiopathic PD among 1,808 Danish patients who were diagnosed in 1996-2009 and matched to 1,876 randomly selected population controls. Although there was a downward trend in duration of smoking, this was not observed for daily tobacco consumption. A moderate intake of caffeine (3.1-5 cups/day) was associated with a lower odds ratio for PD (0.45, 95% confidence interval: 0.34, 0.62), as was a moderate intake of alcohol (3.1-7 units/week) (odds ratio = 0.60, 95% confidence interval: 0.58, 0.84); a higher daily intake did not reduce the odds further. When these behaviors were studied in combination with smoking, the odds ratios were lower than those for each one alone. Compared with never smokers with no family history of PD, never smokers who did have a family history had an odds ratio of 2.81 (95% confidence interval: 1.91, 4.13); for smokers with a family history, the odds ratio was 1.60 (95% confidence interval: 1.15, 2.23). In conclusion, duration of smoking seems to be more important than intensity in the relationship between smoking and idiopathic PD. The finding of lower risk estimates for smoking in combination with caffeine or alcohol requires further confirmation.

Occupational history of night shift work and Parkinson's disease in Denmark

OBJECTIVES

We investigated whether working night shifts was associated with the risk of Parkinson's disease (PD).

METHODS

Between January 2008 and December 2010, we recruited 1808 patients with a confirmed diagnosis of idiopathic PD from Denmark and 1876 population controls matched by year of birth and gender. Information on lifelong occupational history, including information on night work, smoking, caffeine and alcohol consumption habits, and family history of PD was collected through structured telephone interviews.

RESULTS

Overall, there was no association between a history of night shift work and PD [odds ratio (OR) for any type of night work (ie, either permanent or rotating night work) 1.01, 95% confidence interval (95% CI) 0.86-1.21]. Compared with persons who never worked night shifts, risks of those with longer durations of night work did not appear to differ (OR <10 years=0.95, 95% CI 0.75-1.19, OR 10-19 years= 1.09, 95% CI 0.77-1.53, OR ≥20 years=1.05, 95% CI 0.81-1.37, P for trend=0.23). Associations were similar among men and women.

CONCLUSIONS

These data suggest that working night shifts is not associated with PD or that low tolerance for night shift work is an early marker of PD. Due to the novel and exploratory nature of these findings, confirmation is needed.

The role of TREM2 R47H as a risk factor for Alzheimer's disease, frontotemporal lobar degeneration, amyotrophic lateral sclerosis, and Parkinson's disease

A rare variant in TREM2 (p.R47H, rs75932628) was recently reported to increase the risk of Alzheimer's disease (AD) and, subsequently, other neurodegenerative diseases, i.e. frontotemporal lobar degeneration (FTLD), amyotrophic lateral sclerosis (ALS), and Parkinson's disease (PD). Here we comprehensively assessed TREM2 rs75932628 for association with these diseases in a total of 19,940 previously untyped subjects of European descent. These data were combined with those from 28 published data sets by meta-analysis. Furthermore, we tested whether rs75932628 shows association with amyloid beta (Aβ42) and total-tau protein levels in the cerebrospinal fluid (CSF) of 828 individuals with AD or mild cognitive impairment. Our data show that rs75932628 is highly significantly associated with the risk of AD across 24,086 AD cases and 148,993 controls of European descent (odds ratio or OR = 2.71, P = 4.67 × 10(-25)). No consistent evidence for association was found between this marker and the risk of FTLD (OR = 2.24, P = .0113 across 2673 cases/9283 controls), PD (OR = 1.36, P = .0767 across 8311 cases/79,938 controls) and ALS (OR = 1.41, P = .198 across 5544 cases/7072 controls). Furthermore, carriers of the rs75932628 risk allele showed significantly increased levels of CSF-total-tau (P = .0110) but not Aβ42 suggesting that TREM2's role in AD may involve tau dysfunction.

Head injury and risk for Parkinson disease: results from a Danish case-control study

OBJECTIVE

To examine the association between head injuries throughout life and the risk for Parkinson disease (PD) in an interview-based case-control study.

METHODS

We identified 1,705 patients diagnosed with PD at 10 neurologic centers in Denmark in 1996-2009 and verified their diagnoses in medical records. Patients were matched to 1,785 controls randomly selected from the Danish Central Population Register on sex and year of birth. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using unconditional logistic regression.

RESULTS

We observed no association between any head injury before first cardinal symptom and PD (OR 1.02; 95% CI 0.88, 1.19). Examination of number of head injuries (1: OR 1.02; 95% CI 0.87, 1.20; ≥2: OR 1.03; 95% CI 0.72, 1.47) or hospitalization for a head injury (OR 0.89; 95% CI 0.70, 1.12) did not show an association with PD. For 954 study subjects with at least one head injury, there was no evidence of an association between loss of consciousness (OR 0.89; 95% CI 0.67, 1.17), duration of loss of consciousness (≤1 minute: OR 0.93; 95% CI 0.58, 1.49; 1-5 minutes: OR 0.74; 95% CI 0.51, 1.08; ≥5 minutes: OR 0.81; 95% CI 0.53, 1.24), or amnesia (OR 1.31; 95% CI 0.88, 1.95) and risk for PD. Application of a lag time of 10 years between head injury and first cardinal symptom resulted in similar risk estimates.

CONCLUSIONS

The results do not support the hypothesis that head injury increases the risk for PD.

Parkinson disease and smoking revisited: ease of quitting is an early sign of the disease

OBJECTIVE

To assess whether being able to quit smoking is an early marker of Parkinson disease (PD) onset rather than tobacco being "neuroprotective," we analyzed information about ease of quitting and nicotine substitute use.

METHODS

For this case-control study, we identified 1,808 patients with PD diagnosed between 1996 and 2009 from Danish registries, matched 1,876 population controls on sex and year of birth, and collected lifestyle information. We estimated odds ratios and 95% confidence intervals with logistic regression adjusting for matching factors and confounders.

RESULTS

Fewer patients with PD than controls ever established a smoking habit. Among former smokers, those with greater difficulty quitting or using nicotine substitutes were less likely to develop PD, with the risk being lowest among those reporting "extremely difficult to quit" compared with "easy to quit." Nicotine substitute usage was strongly associated with quitting difficulty and duration of smoking, i.e., most strongly among current smokers, followed by former smokers who had used nicotine substitutes, and less strongly among former smokers who never used substitutes.

CONCLUSIONS

Our data support the notion that patients with PD are able to quit smoking more easily than controls. These findings are compatible with a decreased responsiveness to nicotine during the prodromal phase of PD. We propose that ease of smoking cessation is an aspect of premanifest PD similar to olfactory dysfunction, REM sleep disorders, or constipation and suggests that the apparent "neuroprotective" effect of smoking observed in epidemiologic studies is due to reverse causation.

Reproductive factors and Parkinson's disease risk in Danish women

BACKGROUND AND PURPOSE

Parkinson's disease is more common in men than women by a ratio of about 1.5:1 and yet there is no consensus to date as to whether female reproductive factors including hormone use affect Parkinson's disease risk. Our objective was to examine the relationship between Parkinson's disease and female reproductive factors in the largest population-based Parkinson's disease case-control study to date.

METHODS

Seven hundred and forty-three female Parkinson's disease cases diagnosed between 1996 and 2009 were selected from the Danish National Hospital Register, diagnoses confirmed by medical record review, and the cases were matched by birth year to 765 female controls randomly selected from the Danish Civil Registration System. Covariate information was collected in computer-assisted telephone interviews covering an extensive array of topics including reproductive and lifestyle factors.

RESULTS

After adjusting for smoking, caffeine and alcohol use, education, age, and family Parkinson's disease history, inverse associations between Parkinson's disease and early menarche (first period at ≤11 years), oral contraceptives, high parity (≥4 children) and bilateral oophorectomy were found; adjusted odds ratios and 95% confidence limits were respectively 0.68 (0.45-1.03) for early menarche, 0.87 (0.69-1.10) for oral contraceptives, 0.79 (0.59-1.06) for high parity and 0.65 (0.45-0.94) for bilateral oophorectomy. Little support for associations between Parkinson's disease and fertile life length, age at menopause or post-menopausal hormone treatment was found.

CONCLUSIONS

Reproductive factors related to women's early- to mid-reproductive lives appear to be predictive of subsequent Parkinson's disease risk whereas factors occurring later in life seem less important.

Nested case-control study of night shift work and breast cancer risk among women in the Danish military

OBJECTIVES

Growing but limited evidence suggests that night shift work is associated with breast cancer. The authors conducted a nationwide case-control study nested within a cohort of 18,551 female military employees born in 1929-1968 to investigate the risk for breast cancer after night shift work and to explore the role of leisure time sun exposure and diurnal preference.

METHODS

The authors documented 218 cases of breast cancer (1990-2003) and selected 899 age-matched controls from the cohort by incidence density sampling. Information on shift work, sun exposure habits, diurnal preference and other potential confounders was obtained from a structured questionnaire. ORs were estimated by multivariate conditional logistic regression.

RESULTS

Overall, the authors observed an adjusted OR of 1.4 (95% CI 0.9 to 2.1) among women with ever compared with never night shifts. The RR for breast cancer tended to increase with increasing number of years of night shift work (p=0.03) and with cumulative number of shifts (p=0.02),with a neutral risk for fewer than three night shifts per week. The OR for the group with the highest tertile of cumulative exposure was 2.3 (95% CI 1.2 to 4.6). The most pronounced effect of night shift work on breast cancer risk was observed in women with morning chronotype preference and intense night shifts (OR=3.9, 95% CI 1.6 to 9.5). Night shift workers tended to sunbathe more frequently than day workers.

CONCLUSIONS

The results indicate that frequent night shift work increases the risk for breast cancer and suggest a higher risk with longer duration of intense night shifts. Women with morning preference who worked on night shifts tended to have a higher risk than those with evening preference.

Outdoor work and risk for Parkinson's disease: a population-based case-control study

OBJECTIVES

Sunlight is the main contributor to vitamin D in humans. Since inadequate levels of vitamin D have been linked to increased risks for neurodegenerative diseases, we examined whether outdoor work is associated with a reduced risk for Parkinson's disease in a population-based case-control study of Danish men.

METHODS

We identified 3819 men with a primary diagnosis of Parkinson's disease in the period 1995-2006 in the Danish National Hospital Register and selected 19,282 age- and sex-matched population controls at random from the Central Population Register. Information on work history was ascertained from the Danish Supplementary Pension Fund and the Central Population Register. Based on trade grouping codes and job titles, we evaluated the extent of outdoor work of study subjects as a proxy of exposure to sunlight.

RESULTS

Relying on trade grouping codes, we estimated ORs for study subjects with moderate, frequent and maximal outdoor work compared with exclusive indoor work of 0.90 (95% CI 0.78 to 1.02), 0.86 (95% CI 0.75 to 0.99) and 0.72 (95% CI 0.63 to 0.82), respectively, for Parkinson's disease. Reduced risks were also found for Parkinson's disease among outdoor workers based on study subjects' job titles.

CONCLUSIONS

Our findings suggest that men working outdoors have a lower risk for Parkinson's disease. Further studies of measured vitamin D levels in outdoor workers are warranted to clarify a potential inverse association between vitamin D and the risk for Parkinson's disease.

Computer mouse use predicts acute pain but not prolonged or chronic pain in the neck and shoulder

BACKGROUND

Computer use may have an adverse effect on musculoskeletal outcomes. This study assessed the risk of neck and shoulder pain associated with objectively recorded professional computer use.

METHODS

A computer programme was used to collect data on mouse and keyboard usage and weekly reports of neck and shoulder pain among 2146 technical assistants. Questionnaires were also completed at baseline and at 12 months. The three outcome measures were: (1) acute pain (measured as weekly pain); (2) prolonged pain (no or minor pain in the neck and shoulder region over four consecutive weeks followed by three consecutive weeks with a high pain score); and (3) chronic pain (reported pain or discomfort lasting more than 30 days and "quite a lot of trouble" during the past 12 months).

RESULTS

Risk for acute neck pain and shoulder pain increased linearly by 4% and 10%, respectively, for each quartile increase in weekly mouse usage time. Mouse and keyboard usage time did not predict the onset of prolonged or chronic pain in the neck or shoulder. Women had higher risks for neck and shoulder pain. Number of keystrokes and mouse clicks, length of the average activity period, and micro-pauses did not influence reports of acute or prolonged pain. A few psychosocial factors predicted the risk of prolonged pain.

CONCLUSIONS

Most computer workers have no or minor neck and shoulder pain, few experience prolonged pain, and even fewer, chronic neck and shoulder pain. Moreover, there seems to be no relationship between computer use and prolonged and chronic neck and shoulder pain.

Risk factors for persistent elbow, forearm and hand pain among computer workers

OBJECTIVES

This study examined the influence of work-related and personal factors on the prognosis of "severe" elbow, forearm, and wrist-hand pain among computer users.

METHODS

In a 1-year follow-up study of 6943 computer users, 673 (10%) participants reported "quite a lot" or more trouble due to elbow, forearm, or wrist-hand pain during the 12 months preceding the baseline questionnaire. Pain status (recovery versus persistence) at follow-up was examined in relation to computer work aspects and ergonomic, psychosocial, and personal factors by questionnaire. In addition, data on objectively recorded computer usage were available for 42% of the participants during the follow-up, measured by means of a program (WorkPaceRecorder) installed on their computers.

RESULTS

During the follow-up, two-thirds of the baseline cases improved to some degree, but only one-third experienced substantial improvement. The prognosis was not influenced by mouse or keyboard work (time, speed, micropauses, and average activity periods) or ergonomic workplace conditions. Keyboard times, however, were very low. Pain in other regions was a predictor of persistent arm pain. Except for time pressure, female gender, and type-A behavior, the prognosis seemed independent of psychosocial workplace factors and personal factors. A few cases with severe pain were affected at a level which could be compared to clinical pain conditions.

CONCLUSIONS

Our results do not support the hypothesis that computer work activity or ergonomic conditions influence the prognosis of severe arm pain. This result is somewhat surprising and should be tested in other studies. Pain in other regions implies a poorer prognosis for arm pain.

Does computer use pose an occupational hazard for forearm pain; from the NUDATA study

AIMS

To determine the occurrence of pain conditions and disorders in the forearm and to evaluate risk factors for forearm pain in a cohort of computer workers.

METHODS

A total of 6943 participants with a wide range of computer use and work tasks were studied. At baseline and at one year follow up participants completed a questionnaire. Participants with relevant forearm symptoms were offered a clinical examination. Symptom cases and clinical cases were defined on the basis of self reported pain score and palpation tenderness in the muscles of the forearm.

RESULTS

The seven days prevalence of moderate to severe forearm pain was 4.3%. Sixteen of 296 symptom cases met criteria for being a clinical forearm case, and 12 had signs of potential nerve entrapment. One year incidence of reported symptom cases was 1.3%; no subjects developed new signs of nerve entrapment. Increased risk of new forearm pain was associated with use of a mouse device for more than 30 hours per week, and with keyboard use more than 15 hours per week. High job demands and time pressure at baseline were risk factors for onset of forearm pain; women had a twofold increased risk of developing forearm pain. Self reported ergonomic workplace factors at baseline did not predict future forearm pain.

CONCLUSION

Intensive use of a mouse device, and to a lesser extent keyboard usage, were the main risk factors for forearm pain. The occurrence of clinical disorders was low, suggesting that computer use is not commonly associated with any severe occupational hazard to the forearm.

[Infectious arthritis in a patient with rheumatoid arthritis]

Patients with rheumatoid arthritis are at greater risk of developing joint infections than any other group of patients. Diagnosis is often delayed because of the difficulties in distinguishing between a flare-up and a septic affection of the joint. A case of septic arthritis with multiple joint involvement and lethal outcome despite extensive antibiotic treatment and successive surgical procedures is presented. The patient developed osteomyelitis and multiple organ failure. In order to reduce morbidity and mortality from septic arthritis, early joint puncture and subsequent antibiotic treatment is essential.

[Reconstructive joint surgery and rheumatoid arthritis. Status over a developing field]

Rheumatoid arthritis has a prevalence of between 1% and 2%. The majority of patients face the prospect of surgical treatment of joints, that do not respond to medical treatment. With respect to the extensive development in joint surgery during the last decade, today's recommendations for surgical treatment of the individual joints are surveyed.

New-building occupancy. The role of nursing staff development

Orienting hospital staff to a new patient care facility presents many unique challenges for the Nursing Staff Development Department. Today's healthcare climate demands that staff orientation to a new facility be done quickly and with few disruptions to patient care. Nursing staff development specialists are well positioned to lead this process. Their expertise in program design, implementation and evaluation, problem solving and communication skills, and ability to view the learning needs of hospital staff holistically are vital to a successful facility move. This article will describe the opening of a new 150-bed inpatient facility in a large acute rehabilitation center. The principles used by the Nursing Staff Development Department in this new facility orientation process can be applied in multiple health care settings.

[Synovectomy in rheumatoid arthritis]

Surgical synovectomy in the treatment of rheumatoid arthritis has been performed for more than a 100 years, and yet the definite indication has not been made clear. Synovectomy has a convincing, but mostly time-limited effect on pain and articular hydrops, but the radiological progression continues almost undisturbed. Histological evaluation of the regenerating synovial membrane has now shown a tendency towards reversing to baseline within about a year. The difficulties in evaluating the operation are caused by the lack of comparable randomized studies performed on large populations, treated in a double-blind fashion and examined in cooperation between surgeon and rheumatologist.

Benefits of training physicians in advanced cardiac life support

Unexpected cardiopulmonary arrests occur commonly both in the prehospital setting and in the course of hospital care. Survival after prehospital arrest is improved if bystanders and paramedics are trained in basic and advanced cardiac life support. However, within the hospital, the bystanders are the physicians; it is not known if life support training of these hospital-based physician bystanders leads to improved survival. Therefore, we reviewed the outcome of resuscitation attempts in a teaching hospital during two matching six-month periods, before (period 1) and after (period 2) institution of a mandatory course in Advanced Cardiac Life Support (ACLS) for medical houseofficers. It was concluded that survival after inhospital cardiopulmonary arrest is significantly increased if house officers who staff the Code teams are trained in ACLS.