Sex-specific effects of subthalamic nucleus stimulation on pain in Parkinson's disease

OBJECTIVE

Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is known to reduce motor symptoms of Parkinson's disease (PD). The effects of DBS on various nonmotor symptoms often differ from patient to patient. The factors that determine whether or not a patient will respond to treatment have not been elucidated. Here, the authors evaluated sex differences in pain relief after DBS for PD.

METHODS

The authors prospectively evaluated 20 patients preoperatively and postoperatively after bilateral STN DBS with the validated numeric rating scale (NRS), Revised Oswestry Disability Index for low-back pain (RODI), and King's Parkinson's Disease Pain Scale (KPDPS) and assessed the impact of sex as a biological variable.

RESULTS

The cohort consisted of 6 female and 14 male patients with a mean duration of 11.8 ± 2.0 months since DBS surgery. Females were significantly older (p = 0.02). Covariate analysis, however, showed no effect of age, stimulation settings, or other confounding variables. KPDPS total scores statistically significantly improved only among males (p < 0.001). Males improved more than females in musculoskeletal and chronic subsets of the KPDPS (p = 0.03 and p = 0.01, respectively). RODI scores significantly improved in males but not in females (p = 0.03 and p = 0.30, respectively). Regarding the NRS score, the improvements seen in both sexes in NRS were not significant.

CONCLUSIONS

Although it is well recognized that pain complaints in PD are different between men and women, this study is unique in that it examines the sex-specific DBS effects on this symptom. Considering sex as a biological variable may have important implications for DBS pain outcome studies moving forward.

Factors contributing to the success of folic acid public health campaigns

BACKGROUND

Studies in the 1990s have found that periconceptional dietary folate, supplementation of folic acid or supplemental multivitamins containing folic acid, help prevent neural tube defect (NTDs) if taken at the right time. This literature review assesses the extant folic acid public health campaigns literature and identifies some common variables used in folic acid consumption campaign evaluations.

METHODS

This review was part of a larger study that searched PUBMED, PsycINFO and Embase from 1976 to 2010 to identify articles related to the psychosocial and economic impact of NTDs (especially spina bifida) on patients and caregivers.

RESULTS

Awareness of folic acid levels prior to conception improved post-campaign from 6 to 41%. Knowledge about consumption and correct periconceptional use of folic acid also improved. However, in most studies more than 50% of women did not take folic acid as prescribed. Many factors were associated with or without taking folic acid post-campaign, including incomplete outreach, prior awareness and knowledge, closeness to pregnancy, demographics and other personal characteristics.

CONCLUSIONS

Sustained campaigning to maintain awareness about and promote periconceptional consumption of folic acid in order to reduce the incidence of NTDs is clearly needed. Additional initiatives could complement existing public health strategies.

Transpecific microsatellites for hard pines

Microsatellites are difficult to recover from large plant genomes so cross-specific utilisation is an important source of markers. Fifty microsatellites were tested for cross-specific amplification and polymorphism to two New World hard pine species, slash pine ( Pinus elliottii var. elliottii) and Caribbean pine ( P. caribaea var. hondurensis). Twenty-nine (58%) markers amplified in both hard pine species, and 23 of these 29 were polymorphic. Soft pine (subgenus Strobus) microsatellite markers did amplify, but none were polymorphic. Pinus elliottii var. elliottii and P. caribaea var. hondurensis showed mutational changes in the flanking regions and the repeat motif that were informative for Pinus spp. phylogenetic relationships. Most allele length variation could be attributed to variability in repeat unit number. There was no evidence for ascertainment bias.

Demographics, treatment seeking, and diagnoses of anxiety support group participants

Two peer-led anxiety disorder support groups were surveyed to ascertain characteristics of individuals seeking the services of these groups. Both groups had received information and consultation from the Anxiety Disorders Association of America. One hundred and eighty-four individuals were interviewed for diagnosis by structured clinical interview; demographics and treatment-seeking behaviors were ascertained by self-report questionnaires. Both groups surveyed were composed of more females than males and were predominantly Caucasian. Treatment was most frequently sought from psychiatrists, psychologists, and family doctors. One fourth of the sample had sought help for anxiety in a hospital emergency room. Eighty-eight subjects (94%) at the Dallas site and 57 subjects (61%) at the Durham site met criteria for at least one current anxiety or affective disorder. More than half of those who met criteria for current panic disorder with agoraphobia also met criteria for at least one other anxiety disorder, or for major depression. Approximately one third of each support group met criteria for current social phobia. Severity of social phobia symptoms was assessed by four scales. An increased risk of substance abuse was noted for individuals with a diagnosis of social phobia, as compared with diagnoses of other anxiety disorders.

Occurrence of neoplasia in patients with rheumatoid arthritis enrolled in a DMARD Registry. Rheumatoid Arthritis Azathioprine Registry Steering Committee

The Rheumatoid Arthritis Azathioprine Registry (RAAR) was established in 1982 to examine the safety of azathioprine (AZA) and other disease modifying agents (DMARD) in the treatment of RA. In yearly followup over the past 7 years, 20 malignant conditions have been reported in 530 DMARD treated adult patients with RA. Incidence density ratios (IDR) and standardized morbidity ratios (SMR) were calculated to assess cancer risk. For all cancers the SMR was 1.52 (95% CI 0.90-2.60). For men the SMR was 1.71 (95% CI 0.84-3.52); for women the SMR was 1.52 (95% CI 0.89-2.60). Adjusted for age, the IDR was highest in the 70-79-year-old study population (3.41). The age and sex adjusted SMR for lymphoproliferative disorders and myeloma was 8.05 (95% CI 3.30-20.81). The SMR for lung cancer (n = 6) was also increased (3.37; 95% CI 1.58-7.34). Compared with the general population, patients with RA requiring DMARD therapy may be at increased risk of malignancy, particularly lymphoproliferative disorders. The RAAR is an important prospective technique which will ultimately permit assessment of neoplasia risk by type and duration of DMARD therapy.

Effects of Vasocon-A in the allergen challenge model of acute allergic conjunctivitis

The ophthalmic combination product of 0.05% naphazoline hydrochloride and 0.5% antazoline phosphate (Vasocon-A) was evaluated as an antiallergic agent in 100 subjects with a known allergic history to cat dander, ragweed, or bluegrass pollen. Three independent study sites were used. The allergen challenge model of acute allergic conjunctivitis was selected to assess the agent as it provided a standardized and precise way to measure drug effectiveness for this indication. In a double-masked randomized fashion, the subjects were assigned to one of three groups that received one drop of Vasocon-A in one eye and one drop of either 0.05% naphazoline (group 1), 0.5% antazoline (group 2), or placebo (group 3) in the contralateral eye. After 10 minutes, the dose of allergen shown to elicit a 2+ redness and itching reaction was instilled bilaterally. Signs and symptoms of allergic conjunctivitis were evaluated after 3, 5, and 10 minutes. Subjects were then rechallenged 2 hours after drug administration to assess the duration of action of the agents. Vasocon-A was found to significantly inhibit all five major signs and symptoms of allergic conjunctivitis: itching, redness, chemosis, lid swelling, and tearing, for more than 85% of the comparisons when compared over time with placebo, naphazoline alone, or antazoline alone. The results of this study indicate that the combination of naphazoline and antazoline was more effective in inhibiting redness than naphazoline and more effective in inhibiting itching than antazoline. These findings support the use of such a combination for the treatment of allergic conjunctivitis.

Dietary fats and cancer

The mono-unsaturated non-essential fatty acid oleic acid (OA) has been shown to stimulate malignant cell proliferation in culture significantly. In contrast, the essential fatty acids (EFAs) linoleic acid (LA) and alpha-linolenic acid (ALA) and their longer chain metabolic derivatives have been shown to have potent proliferation suppressive effects on malignant cells in culture. OA is normally synthesized in the body and present in most vegetable oils and therefore also in most experimental polyunsaturated fatty acid diets used for assessing the effects of dietary fatty acids on tumorigenesis in rats. Dietary OA could therefore specifically account for the general observation that diets containing polyunsaturated fatty acids (PUFAs) are tumorigenic (1). It has been repeatedly demonstrated that many EFAs and EFA metabolites suppress proliferation of a wide range of malignant cells in culture. These cytotoxic effects of EFAs do not inhibit the proliferation of nonmalignant cultured cells. The EFAs which have proliferation-suppression activities are components of cell membranes and many are also eicosanoid precursors. It is proposed that the membranes of malignant cells are inherently unstable. Thus the EFAs may have effects which either fluidise or stabilise these membranes. This results in either cytolysis or inhibition of proliferation. The relative quantities of the different EFAs may be critical for these effects. Eicosanoid metabolites may further compound these actions. It is suggested that one pathway for these actions could be a metabolic imbalance of EFA metabolites and their eicosanoid products. This would arise due to a combination of inhibited desaturase enzymes and a concomitant free cellular supply of dietary arachidonic acid (AA). This imbalance also could be causally involved in the promotion of malignancy. A simple procedure, which only involves dietary supplementation with gamma-linolenic acid (GLA) and eicosapentaenoic acid (EPA), is proposed as prophylaxis against the possible tumorigenic effect of dietary fats. "By some estimates, as much as 90% of all cancer in humans has been attributed to various environmental factors, including diet. The evidence reviewed by the committee suggests that cancers of most of the major sites are influenced by dietary patterns. The committee concluded that of all the dietary components it studied, the combined epidemiological and experimental evidence is most suggestive for a causal relationship between fat intake and the occurrence of cancer" - (1).

Peer review in community mental health

The paper discusses the medical origins of the peer review legislation and its adaptation to community mental health. Three models of peer eview are presented which could be used in community mental health centers. They are the problem model, the sequential model, and the Psychiatric Utilization Review and Evaluation Project (PURE) model. All three require a review of records by a committee of respected clinical staff, regardless of profession.