Respiratory infectious burden in a cohort of antibody deficiency patients treated with immunoglobulin replacement therapy: The impact of lung pathology and gastroesophageal reflux disease

Background

Antibody deficiencies result from reduced immunoglobulin levels and function, increasing susceptibility to, primarily, bacterial infection. Primary antibody deficiencies comprise intrinsic defects in B-cell physiology, often due to inherited errors. Hematological malignancies or B-cell suppressive therapy are major causes of secondary antibody deficiency. Although immunoglobulin replacement therapy (IGRT) reduces infectious burden in antibody deficiency patients, respiratory tract infections remain a significant health burden. We hypothesize that lung pathology and gastroesophageal reflux disease (GORD) increase the risk of pneumonia in antibody deficiency patients, as in the general population.

Objective

For our cohort of patients with primary antibody deficiency and secondary antibody deficiency, we reviewed their respiratory infectious burden and the impact of lung pathologies and GORD.

Methods

The medical records of 231 patients on IGRT at a tertiary referral center, from October 26, 2014, to February 19, 2021, were reviewed to determine microbial isolates from sputum samples and prevalence of common lung pathologies and GORD.

Results

Haemophilus and Pseudomonas species represent a large infectious burden, being identified in 30.2% and 21.4% of sputum samples demonstrating growth, respectively; filamentous fungal and mycobacterial infections were rare. Diagnosed lung pathology increased the proportion of patients with Pseudomonas, Klebsiella, Stenotrophomonas, and Candida species isolated in their sputum, and diagnosed GORD increased the proportion with Enterobacter and Candida species isolated.

Conclusions

Bacterial respiratory infectious burden remains in primary antibody deficiency and secondary antibody deficiency despite IGRT. Lung pathologies encourage growth of species less susceptible to IGRT, so specialist respiratory medicine input and additional treatments such as inhaled antibiotics are indicated to optimize respiratory outcomes.

A National Survey of Hereditary Angioedema and Acquired C1 Inhibitor Deficiency in the United Kingdom

BACKGROUND

Detailed demographic data on people with hereditary angioedema (HAE) and acquired C1 inhibitor deficiency in the United Kingdom are relatively limited. Better demographic data would be beneficial in planning service provision, identifying areas of improvement, and improving care.

OBJECTIVE

To obtain more accurate data on the demographics of HAE and acquired C1 inhibitor deficiency in the United Kingdom, including treatment modalities and services available to patients.

METHODS

A survey was distributed to all centers in the United Kingdom that look after patients with HAE and acquired C1 inhibitor deficiency to collect these data.

RESULTS

The survey identified 1152 patients with HAE-1/2 (58% female and 92% type 1), 22 patients with HAE with normal C1 inhibitor, and 91 patients with acquired C1 inhibitor deficiency. Data were provided by 37 centers across the United Kingdom. This gives a minimum prevalence of 1:59,000 for HAE-1/2 and 1:734,000 for acquired C1 inhibitor deficiency in the United Kingdom. A total of 45% of patients with HAE were on long-term prophylaxis (LTP) with the most used medication being danazol (55% of all patients on LTP). Eighty-two percent of patients with HAE had a home supply of acute treatment with C1 inhibitor or icatibant. A total of 45% of patients had a supply of icatibant and 56% had a supply of C1 inhibitor at home.

CONCLUSIONS

Data obtained from the survey provide useful information about the demographics and treatment modalities used in HAE and acquired C1 inhibitor deficiency in the United Kingdom. These data are useful for planning service provision and improving services for these patients.

Rituximab Associated Hypogammaglobulinemia in Autoimmune Disease

Objective

To evaluate the characteristics of patients with autoimmune disease with hypogammaglobulinemia following rituximab (RTX) and describe their long-term outcomes, including those who commenced immunoglobulin replacement therapy.

Methods

Patients received RTX for autoimmune disease between 2003 and 2012 with immunoglobulin G (IgG) <7g/L were included in this retrospective series. Hypogammaglobulinemia was classified by nadir IgG subgroups of 5 to <7g/L (mild), 3 to <5g/L (moderate) and <3g/L (severe). Characteristics of patients were compared across subgroups and examined for factors associated with greater likelihood of long term hypogammaglobulinemia or immunoglobulin replacement.

Results

142 patients were included; 101 (71%) had anti-neutrophil cytoplasm antibody (ANCA) associated vasculitis (AAV), 18 (13%) systemic lupus erythematosus (SLE) and 23 (16%) other conditions. Mean follow-up was 97.2 months from first RTX. Hypogammaglobulinemia continued to be identified during long-term follow-up. Median time to IgG <5g/L was 22.5 months. Greater likelihood of moderate hypogammaglobulinemia (IgG <5g/L) and/or use of immunoglobulin replacement therapy at 60 months was observed in patients with prior cyclophosphamide exposure (odds ratio (OR) 3.60 [95% confidence interval (CI) 1.03 – 12.53], glucocorticoid use at 12 months [OR 7.48 (95% CI 1.28 – 43.55], lower nadir IgG within 12 months of RTX commencement [OR 0.68 (95% CI 0.51 – 0.90)] and female sex [OR 8.57 (95% CI 2.07 – 35.43)]. Immunoglobulin replacement was commenced in 29/142 (20%) and associated with reduction in infection rates, but not severe infection rates.

Conclusion

Hypogammaglobulinemia continues to occur in long-term follow-up post-RTX. In patients with recurrent infections, immunoglobulin replacement reduced rates of non-severe infections.

The Effective Management of Idiopathic Intracranial Hypertension Delivered by In-person and Virtual Group Consultations: Results and Reflections from a Phase One Service Delivery

The increasing incidence of idiopathic intracranial hypertension (IIH) with the obesity epidemic is leading to increased pressures on service capacity. Evidence shows that group consultations (GCs) deliver effective, person-centred healthcare, but the feasibility for IIH is unknown. We set out to develop and test a safe and effective GC service for IIH. Through an interactive approach, we co-designed a bespoke in-person and virtual GC model, where patients are reviewed in a group setting. Improvements were made following each session following patient input and team reflections. Outcomes measured included patient satisfaction, self-perceived health literacy, and successful implementation of the GCs. During the pilot, eight in-person GCs were delivered: once-monthly (Oct-Dec 2019), then twice-monthly (Jan-Feb 2020). Feedback was received from 49/53 patients. 100% felt more satisfied and heard, 100% felt more involved in decision-making, 98% had a better understanding of their condition, 96% felt more able to cope with their condition and keep themselves healthy, 94% rated this as a positive experience, and 90% reported improved access and more time with their clinician compared with existing 1:1 appointments. Since September 2020, in response to the COVID-19 pandemic, we transitioned to weekly virtual GCs, receiving overwhelmingly positive feedback (median scores: patient satisfaction 9.5/10; being listened to by clinician 10/10; involved by clinician in treatment decisions 10/10; clinician explanation of treatment 10/10; and opportunity to discuss condition or treatment 10/10). GCs are safe and effective for IIH, and preferred in our patient cohort. This allowed ongoing high-quality, person-centred care despite challenges from the COVID-19 pandemic.

Bi-allelic Loss-of-Function CACNA1B Mutations in Progressive Epilepsy-Dyskinesia

The occurrence of non-epileptic hyperkinetic movements in the context of developmental epileptic encephalopathies is an increasingly recognized phenomenon. Identification of causative mutations provides an important insight into common pathogenic mechanisms that cause both seizures and abnormal motor control. We report bi-allelic loss-of-function CACNA1B variants in six children from three unrelated families whose affected members present with a complex and progressive neurological syndrome. All affected individuals presented with epileptic encephalopathy, severe neurodevelopmental delay (often with regression), and a hyperkinetic movement disorder. Additional neurological features included postnatal microcephaly and hypotonia. Five children died in childhood or adolescence (mean age of death: 9 years), mainly as a result of secondary respiratory complications. CACNA1B encodes the pore-forming subunit of the pre-synaptic neuronal voltage-gated calcium channel Ca_v2.2/N-type, crucial for SNARE-mediated neurotransmission, particularly in the early postnatal period. Bi-allelic loss-of-function variants in CACNA1B are predicted to cause disruption of Ca²⁺ influx, leading to impaired synaptic neurotransmission. The resultant effect on neuronal function is likely to be important in the development of involuntary movements and epilepsy. Overall, our findings provide further evidence for the key role of Ca_v2.2 in normal human neurodevelopment.

Comprehensive Cancer-Predisposition Gene Testing in an Adult Multiple Primary Tumor Series Shows a Broad Range of Deleterious Variants and Atypical Tumor Phenotypes

Multiple primary tumors (MPTs) affect a substantial proportion of cancer survivors and can result from various causes, including inherited predisposition. Currently, germline genetic testing of MPT-affected individuals for variants in cancer-predisposition genes (CPGs) is mostly targeted by tumor type. We ascertained pre-assessed MPT individuals (with at least two primary tumors by age 60 years or at least three by 70 years) from genetics centers and performed whole-genome sequencing (WGS) on 460 individuals from 440 families. Despite previous negative genetic assessment and molecular investigations, pathogenic variants in moderate- and high-risk CPGs were detected in 67/440 (15.2%) probands. WGS detected variants that would not be (or were not) detected by targeted resequencing strategies, including low-frequency structural variants (6/440 [1.4%] probands). In most individuals with a germline variant assessed as pathogenic or likely pathogenic (P/LP), at least one of their tumor types was characteristic of variants in the relevant CPG. However, in 29 probands (42.2% of those with a P/LP variant), the tumor phenotype appeared discordant. The frequency of individuals with truncating or splice-site CPG variants and at least one discordant tumor type was significantly higher than in a control population (χ2 = 43.642; p ≤ 0.0001). 2/67 (3%) probands with P/LP variants had evidence of multiple inherited neoplasia allele syndrome (MINAS) with deleterious variants in two CPGs. Together with variant detection rates from a previous series of similarly ascertained MPT-affected individuals, the present results suggest that first-line comprehensive CPG analysis in an MPT cohort referred to clinical genetics services would detect a deleterious variant in about a third of individuals.

A novel de novo activating mutation in STAT3 identified in a patient with common variable immunodeficiency (CVID)

Common variable immunodeficiency (CVID) is characterised by repeated infection associated with primary acquired hypogammaglobulinemia. CVID frequently has a complex aetiology but, in certain cases, it has a monogenic cause. Recently, variants within the gene encoding the transcription factor STAT3 were implicated in monogenic CVID. Here, we describe a patient presenting with symptoms synonymous with CVID, who displayed reduced levels of IgG and IgA, repeated viral infections and multiple additional co-morbidities. Whole-exome sequencing revealed a de novo novel missense mutation in the coiled-coil domain of STAT3 (c.870A>T; p.K290N). Accordingly, the K290N variant of STAT3 was generated, and a STAT3 responsive dual-luciferase reporter assay revealed that the variant strongly enhances STAT3 transcriptional activity both under basal and stimulated (with IL-6) conditions. Overall, these data complement earlier studies in which CVID-associated STAT3 mutations are predicted to enhance transcriptional activity, suggesting that such patients may respond favourably to IL-6 receptor antagonists (e.g. tocilizumab).

Abstract P2-13-04: Clinical outcome and patient satisfaction with the use of bovine-derived acellular dermal matrix (SurgiMendTM) in implant-based immediate reconstruction following skin sparing mastectomy: A prospective observational study

The advent of acellular dermal matrix devices (ADMs) has facilitated immediate breast reconstruction (IBR) with mammary implants following skin sparing mastectomy (SSM) for breast cancer treatment or risk reduction.

This is a prospective observational single institution study of 118 consecutive patients undergoing a total of 164 SSM and IBR procedures using an implant and bovine-derived ADM (SurgiMend) for breast cancer or risk reduction purposes during 2012-2014. The primary endpoint was the explantation rate and secondary endpoints included patient quality of life, patient satisfaction, objective assessment of aesthetic outcome, surgical complications, recurrence and mortality.

The mean age of the patients was 50.1 years (median age of 48, range of 27-78). Median follow up time was 21 months (mean of 21.4 months, range of 2-40 months). 46 patients had a bilateral SSM and IBR, 5 of whom had bilateral breast cancer and 3 for risk reduction due to a significant genetic mutation. The remaining 37 patients had unilateral breast cancer and a contralateral risk reducing mastectomy. 27 (37.5%) of the 72 patients who had unilateral SSM underwent contralateral adjustment procedures to optimise symmetry, including 9 augmentation mammoplasty, 12 mastopexy and 4 reduction mammaplasty procedures and 2 combined augmentation-mastopexies. 61 patients (51.7%) received chemotherapy, 5 of whom had primary systemic therapy prior to surgery. 32 (27.1%) patients received radiotherapy (10 patients had prior radiotherapy and 22 patients had post mastectomy radiation: PMR). Those with ER positive disease received hormonal therapy. Those with Her2 positivity received Herceptin +/- Pertuzumab.

Over the study period, 2 implants had to be removed resulting in an explantation rate of 1.2%. Overall, wound complications were observed in 6 (3.7%) cases. There were 2 cases of local recurrence (1.7%), one distant recurrence (0.8%) and one patient died of metastatic breast cancer (0.8%). Overall survival was 99.2% and locoregional disease free survival (LRFS) was 98.3%. One patient (0.8%) developed a mild inflammatory reaction secondary to the underlying mesh. Wound complications were observed in 3 other patients (2 haematomas and wound dehiscence/persistent seroma requiring implant replacement).

Patient satisfaction with the procedure was very high. The mean Breast Q Score was 85 and mean overall patient satisfaction was 9 out of a possible 10. The mean objective assessment score was 8.9 out of a possible 10 and the mean subjective capsular contracture severity score was 2.9 out of 10.

In patients undergoing reoperations, the incorporation rate of the mesh was found to be very high almost approaching 95%.

SurgiMendTM is an effective adjunct to IBR using implants following SSM for breast cancer or risk reduction, with a very low rate of implant loss and a high level of patient satisfaction. Furthermore, this ADM seems to incorporate readily and is associated with a very low incidence of inflammatory reactions. Neither prior radiotherapy nor PMR radiation represents a contraindication to its use.

Citation Format: Wazir U, Kasem A, Headon H, Choy C, Manson A, Heeney J, Mead O, Mokbel K. Clinical outcome and patient satisfaction with the use of bovine-derived acellular dermal matrix (SurgiMendTM) in implant-based immediate reconstruction following skin sparing mastectomy: A prospective observational study. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P2-13-04.

Immune deficiency: changing spectrum of pathogens

Current UK national standards recommend routine bacteriology surveillance in severe antibody-deficient patients, but less guidance exists on virology screening and viral infections in these patients. In this retrospective audit, we assessed the proportion of positive virology or bacteriology respiratory and stool samples from patients with severe, partial or no immune deficiency during a 2-year period. Medical notes were reviewed to identify symptomatic viral infections and to describe the course of persistent viral infections. During the 2-year period, 31 of 78 (39·7%) severe immune-deficient patients tested had a positive virology result and 89 of 160 (55.6%) had a positive bacteriology result. The most commonly detected pathogens were rhinovirus (12 patients), norovirus (6), Haemophilus influenzae (24), Pseudomonas spp. (22) and Staphylococcus aureus (21). Ninety-seven per cent of positive viral detection samples were from patients who were symptomatic. Low serum immunoglobulin IgA levels were more prevalent in patients with a positive virology sample compared to the total cohort (P = 0·0078). Three patients had persistent norovirus infection with sequential positive isolates for 9, 30 and 16 months. Virology screening of symptomatic antibody-deficient patients may be useful as a guide to anti-microbial treatment. A proportion of these patients may experience persistent viral infections with significant morbidity.

Quantifying the impact of dyskinesias in PD: the PDYS-26: a patient-based outcome measure

BACKGROUND

Drug-induced dyskinesias are a common and disabling clinical problem in the long-term management of Parkinson disease (PD). Their management and the development of new treatments rely on rigorous and meaningful dyskinesia measurement. Although clinician-based approaches exist, patient-based measures are limited.

METHOD

Potential rating scale items concerning daily activities affected by dyskinesias were generated from patients, literature review, and expert opinion. The resulting 42-item questionnaire was administered to 98 patients known to have problematic dyskinesias; 72 patients were invited to complete it twice for test-retest reliability (trt). Rasch analysis guided scale development. Results were cross-validated using traditional psychometric methods by examining scaling assumptions (item means and variances, item-total correlations), reliability (Cronbach alpha, trt), and validity (factor analysis). External validation was performed against standard dyskinesia measures: blinded video rating using modified Goetz and Abnormal Involuntary Movements Scales (AIMS), and Unified PD Rating Scale (UPDRS) questions 32-34.

RESULTS

Response rates were high. Fourteen items were removed because of high missing data. The remaining items were Rasch analyzed. Two items were removed because of misfit. The resulting 26 items formed a clinically and statistically conformable set. Traditional psychometric criteria were satisfied and external validation showed good correlation with the UPDRS items and moderate to good correlation with objective dyskinesia measures.

CONCLUSION

The 26-item Parkinson Disease Dyskinesia Scale (PDYS-26) satisfied multiple criteria for reliable and valid measurement. Correlations with objective measures suggest that it captures related but not identical constructs. As a patient-derived scale that generates linear measurements, it could complement existing clinician-based dyskinesia measures.

Mucuna pruriens in Parkinson's disease: a double blind clinical and pharmacological study

BACKGROUND

The seed powder of the leguminous plant, Mucuna pruriens has long been used in traditional Ayurvedic Indian medicine for diseases including parkinsonism. We have assessed the clinical effects and levodopa (L-dopa) pharmacokinetics following two different doses of mucuna preparation and compared them with standard L-dopa/carbidopa (LD/CD).

METHODS

Eight Parkinson's disease patients with a short duration L-dopa response and on period dyskinesias completed a randomised, controlled, double blind crossover trial. Patients were challenged with single doses of 200/50 mg LD/CD, and 15 and 30 g of mucuna preparation in randomised order at weekly intervals. L-dopa pharmacokinetics were determined, and Unified Parkinson's Disease Rating Scale and tapping speed were obtained at baseline and repeatedly during the 4 h following drug ingestion. Dyskinesias were assessed using modified AIMS and Goetz scales.

RESULTS

Compared with standard LD/CD, the 30 g mucuna preparation led to a considerably faster onset of effect (34.6 v 68.5 min; p = 0.021), reflected in shorter latencies to peak L-dopa plasma concentrations. Mean on time was 21.9% (37 min) longer with 30 g mucuna than with LD/CD (p = 0.021); peak L-dopa plasma concentrations were 110% higher and the area under the plasma concentration v time curve (area under curve) was 165.3% larger (p = 0.012). No significant differences in dyskinesias or tolerability occurred.

CONCLUSIONS

The rapid onset of action and longer on time without concomitant increase in dyskinesias on mucuna seed powder formulation suggest that this natural source of L-dopa might possess advantages over conventional L-dopa preparations in the long term management of PD. Assessment of long term efficacy and tolerability in a randomised, controlled study is warranted.

Skipping of exon 9 of human CFTR in YAC-transgenic mice

Exon 9 of the human gene CFTR is skipped in some mRNA transcripts in human tissues. The level of skipping correlates with the number of TG's and T's in the 5' splice acceptor of exon 9. Poorly spliced alleles are associated with mild cystic fibrosis related phenotypes. Here we describe transgenic mice carrying a yeast artificial chromosome (YAC) with the intact human gene CFTR. When the YAC carries 10 TG's and 7 T's at the splice acceptor, there is about 50% skipping of exon 9 in most tissues, whereas 12 TG's and 5 T's give about 90% skipping. The level of skipping is quite uniform over many tissues, except the testis, in which there is a much higher level of correct splicing. These mice confirm that the TG(m)T(n) polymorphism has an effect on splicing and should be valuable for studying this phenomenon.

Diabetes knowledge--are patients getting the message?

Diabetes knowledge in a multi-ethnic population was assessed in 161 insulin treated diabetic patients using a 21-point multiple choice questionnaire translated into the appropriate languages. Our data showed a significant difference in diabetes knowledge related to ethnicity, being less in Asians and Afro-Caribbeans groups compared to Caucasians. In all groups there was a negative correlation with age, with older adults achieving lower scores. Gender and duration of disease did not appear to influence knowledge scores. This information has implications for the way in which we deliver our diabetes educational programme to ethnic minority groups and the elderly.

Correlation between varying levels of PMP22 expression and the degree of demyelination and reduction in nerve conduction velocity in transgenic mice

Charcot-Marie-Tooth disease type 1A is most commonly caused by a duplication of a 1.5 Mb region of chromosome 17 which includes the peripheral myelin protein 22 gene (PMP22). Over-expression of this gene leads to a hypomyelinating/demyelinating neuropathy and to severely reduced nerve conduction velocity. Previous mouse and rat models have had relatively high levels of expression of the mouse or human PMP22 gene leading to severe demyelination. Here we describe five lines of transgenic mice carrying increasing copies of the human PMP22 gene (one to seven) and expressing increasing levels of the transgene. From histological and electrophysiological observations there appears to be a threshold below which expression of PMP22 has virtually no effect; below a ratio of human/mouse mRNA expression of approximately 0.8, little effect is observed. Between a ratio of 0.8 and 1.5, histological and nerve conduction velocity abnormalities are observed, but there are no behavioural signs of neuropathy. An expression ratio >1.5 leads to a severe neuropathy. A second observation concerns the histology of the different lines; the level of expression does not affect the type of demyelination, but influences the severity of involvement.

Construction of a mouse model of Charcot-Marie-Tooth disease type 1A by pronuclear injection of human YAC DNA

Construction of animal models of human inherited diseases is particularly important for testing gene therapy approaches. Towards this end, we constructed a mouse model for Charcot-Marie-Tooth disease type 1A by pronuclear injection of a YAC containing the human PMP22 gene. In one transgenic line, the YAC DNA is integrated in about eight copies and the PMP22 gene is strongly expressed to give a peripheral neuropathy closely resembling the human pathology. The disorder is dominant, causes progressive weakness of the hind legs, and there is severe demyelination in the peripheral nervous system including the presence of onion bulb formations. This approach will be valuable for pathologies produced by over-expression of a gene including trisomy and amplification in cancer. Such models will be particularly useful for testing gene therapy approaches if the transgene is human.

Malnutrition in elderly ambulatory medical patients

Elderly ambulatory persons may be especially susceptible to malnutrition, particularly those who are poor and socially isolated or have comorbid chronic medical diseases. We found that 98 of 2,986 persons aged 60 years or older attending a hospital-based medical practice between 1979 and 1989 weighed less than 45.4 kg (100 lbs). All but 1 of these subjects met criteria for malnutrition as judged against age-specific norms for weight. Thus the prevalence of malnutrition in this sample was 3.25% (95% CI 2.61, 3.89%). Interviews and physical examinations of a subsample (n = 16) revealed that all 16 subjects either met anthropometric-based criteria for malnutrition or were being treated for malnutrition. Of the 98 subjects who weighed less than 45.4 kg, 62 (63.3%; 95% CI 53.8, 72.8%) had comorbid conditions that could have contributed to malnutrition. Physicians did not record a diagnosis of malnutrition or weight loss in 47.9% of subjects (95% CI 38.0, 57.8%) and did not prescribe a nutrition supplement for 76.5% of subjects (95% CI 68.1, 84.9%). Subjects treated with nutrition supplement were more likely to have cancer. These findings suggest that malnutrition, both with and without concomitant major comorbid disease, is relatively frequent among elderly ambulatory patients and that a specific nutritional diagnosis is not made in many cases. We suggest that weight under 45.4 kg in an elderly person is a useful criterion for identifying elderly patients at nutritional risk.

Language concordance as a determinant of patient compliance and emergency room use in patients with asthma

To test the hypothesis that the ability of physicians to speak the same language as asthmatic patients promotes patient compliance and the use of scheduled office appointments in preference to emergency services, the charts of 96 Spanish-speaking patients with asthma were reviewed. Of these patients, 65 were cared for by seven Spanish-speaking bilingual physicians and 31 were cared for by 23 non-Spanish speaking physicians. Compared with patients with language concordant physicians, patients with language discordant physicians were only slightly more likely to omit medication, to miss office appointments, and to make at least one emergency room visit. Subgroup analysis showed that, with extended follow-up, patients cared for by a language discordant physician were more likely to omit medication (rate ratio: 3.24; p = 0.08), more likely to miss office appointments (rate ratio: 3.06; P = 0.01), and were slightly more likely to make an emergency room visit (rate ratio: 2.07; P = 0.12) than patients with language concordant physicians. Cox regression analyses taking account of differences in follow-up time, age, gender, pay-status, and severity of disease confirmed these findings. These data suggest that patient compliance and more cost-effective use of ambulatory care services may be associated with the ability of physicians to speak the same language as their patients.