What, how and who: Cost-effectiveness analyses of COVID-19 vaccination to inform key policies in Nigeria

While safe and efficacious COVID-19 vaccines have achieved high coverage in high-income settings, roll-out remains slow in sub-Saharan Africa. By April 2022, Nigeria, a country of over 200 million people, had only distributed 34 million doses. To ensure the optimal use of health resources, cost-effectiveness analyses can inform key policy questions in the health technology assessment process. We carried out several cost-effectiveness analyses exploring different COVID-19 vaccination scenarios in Nigeria. In consultation with Nigerian stakeholders, we addressed three key questions: what vaccines to buy, how to deliver them and what age groups to target. We combined an epidemiological model of virus transmission parameterised with Nigeria specific data with a costing model that incorporated local resource use assumptions and prices, both for vaccine delivery as well as costs associated with care and treatment of COVID-19. Scenarios of vaccination were compared with no vaccination. Incremental cost-effectiveness ratios were estimated in terms of costs per disability-adjusted life years averted and compared to commonly used cost-effectiveness ratios. Viral vector vaccines are cost-effective (or cost saving), particularly when targeting older adults. Despite higher efficacy, vaccines employing mRNA technologies are less cost-effective due to high current dose prices. The method of delivery of vaccines makes little difference to the cost-effectiveness of the vaccine. COVID-19 vaccines can be highly effective and cost-effective (as well as cost-saving), although an important determinant of the latter is the price per dose and the age groups prioritised for vaccination. From a health system perspective, viral vector vaccines may represent most cost-effective choices for Nigeria, although this may change with price negotiation.

Considering equity in priority setting using transmission models: Recommendations and data needs

OBJECTIVES

Disease transmission models are used in impact assessment and economic evaluations of infectious disease prevention and treatment strategies, prominently so in the COVID-19 response. These models rarely consider dimensions of equity relating to the differential health burden between individuals and groups. We describe concepts and approaches which are useful when considering equity in the priority setting process, and outline the technical choices concerning model structure, outputs, and data requirements needed to use transmission models in analyses of health equity.

METHODS

We reviewed the literature on equity concepts and approaches to their application in economic evaluation and undertook a technical consultation on how equity can be incorporated in priority setting for infectious disease control. The technical consultation brought together health economists with an interest in equity-informative economic evaluation, ethicists specialising in public health, mathematical modellers from various disease backgrounds, and representatives of global health funding and technical assistance organisations, to formulate key areas of consensus and recommendations.

RESULTS

We provide a series of recommendations for applying the Reference Case for Economic Evaluation in Global Health to infectious disease interventions, comprising guidance on 1) the specification of equity concepts; 2) choice of evaluation framework; 3) model structure; and 4) data needs. We present available conceptual and analytical choices, for example how correlation between different equity- and disease-relevant strata should be considered dependent on available data, and outline how assumptions and data limitations can be reported transparently by noting key factors for consideration.

CONCLUSIONS

Current developments in economic evaluations in global health provide a wide range of methodologies to incorporate equity into economic evaluations. Those employing infectious disease models need to use these frameworks more in priority setting to accurately represent health inequities. We provide guidance on the technical approaches to support this goal and ultimately, to achieve more equitable health policies.

USA stockpiling of remdesivir: How should the world respond?

The race to find an effective treatment for coronavirus disease 2019 (COVID-19) is still on, with only two treatment options currently authorized for emergency use and/or recommended for patients hospitalized with severe respiratory symptoms: low-dose dexamethasone and remdesivir. The USA decision to stockpile the latter has resulted in widespread condemnation and in similar action being taken by some other countries. In this commentary we discuss whether stockpiling remdesivir is justified in light of the currently available evidence.

What do we need to know? Data sources to support evidence-based decisions using health technology assessment in Ghana

BACKGROUND

Evidence-based decision-making for prioritising health is assisted by health technology assessment (HTA) to integrate data on effectiveness, costs and equity to support transparent decisions. Ghana is moving towards universal health coverage, facilitated mainly by the National Health Insurance Scheme (NHIS) established in 2003. The Government of Ghana is committed to institutionalising HTA for priority-setting. We aimed to identify and describe the sources of accessible data to support HTA in Ghana.

METHODS

We identified and described data sources encompassing six main domains using an existing framework. The domains were epidemiology, clinical efficacy, costs, health service use and consumption, quality of life, and equity. We used existing knowledge, views of stakeholders, and searches of the literature and internet.

RESULTS

The data sources for each of the six domains vary in extent and quality. Ghana has several large data sources to support HTA (e.g. Demographic Health Surveys) that have rigorous quality assurance processes. Few accessible data sources were available for costs and resource utilisation. The NHIS is a potentially rich source of data on resource use and costs but there are some limits on access. There are some data on equity but data on quality of life are limited.

CONCLUSIONS

A small number of quality data sources are available in Ghana but there are some gaps with respect to HTA based on greater use of local and contextualised information. Although more data are becoming available for monitoring, challenges remain in terms of their usefulness for HTA, and some information may not be available in disaggregated form to enable specific analyses. We support recent initiatives for the routine collection of comprehensive and reliable data that is easily accessible for HTA users. A commitment to HTA will require concerted efforts to leverage existing data sources, for example, from the NHIS, and develop and maintain new data (e.g. local health utility estimates). It will be critical that an overarching strategic and mandatory approach to the collection and use of health information is developed for Ghana in parallel to, and informed by, the development of HTA approaches to support resource allocation decisions. The key to HTA is to use the best available data while being open about its limitations and the impact on uncertainty.

How long has NICE taken to produce Technology Appraisal guidance? A retrospective study to estimate predictors of time to guidance

OBJECTIVES

To assess how long the UK's National Institute for Health and Clinical Excellence's (NICE) Technology Appraisal Programme has taken to produce guidance and to determine independent predictors of time to guidance.

DESIGN

Retrospective time to event (survival) analysis.

SETTING

Technology Appraisal guidance produced by NICE. DATASOURCE: All appraisals referred to NICE by February 2010 were included, except those referred prior to 2001 and a number that were suspended.

OUTCOME MEASURE

Duration from the start of an appraisal (when the scope document was released) until publication of guidance.

RESULTS

Single Technology Appraisals (STAs) were published significantly faster than Multiple Technology Appraisals (MTAs) with median durations of 48.0 (IQR; 44.3-75.4) and 74.0 (IQR; 60.9-114.0) weeks, respectively (p <0.0001). Median time to publication exceeded published process timelines, even after adjusting for appeals. Results from the modelling suggest that STAs published guidance significantly faster than MTAs after adjusting for other covariates (by 36.2 weeks (95% CI -46.05 to -26.42 weeks)) and that appeals against provisional guidance significantly increased the time to publication (by 42.83 weeks (95% CI 35.50 to 50.17 weeks)). There was no evidence that STAs of cancer-related technologies took longer to complete compared with STAs of other technologies after adjusting for potentially confounding variables and only weak evidence suggesting that the time to produce guidance is increasing each year (by 1.40 weeks (95% CI -0.35 to 2.94 weeks)).

CONCLUSIONS

The results from this study suggest that the STA process has resulted in significantly faster guidance compared with the MTA process irrespective of the topic, but that these gains are lost if appeals are made against provisional guidance. While NICE processes continue to evolve over time, a trade-off might be that decisions take longer but at present there is no evidence of a significant increase in duration.

Cost Effectiveness of Controlled-Release Oxybutynin Compared with Immediate-Release Oxybutynin and Tolterodine in the Treatment of Overactive Bladder in the UK, France and Austria

OBJECTIVE

To estimate the cost effectiveness of controlled-release (CR) oxybutynin compared with immediate-release (IR) oxybutynin and tolterodine in the treatment of overactive bladder (OAB) in Austria, France and the UK.

DESIGN AND SETTING

This was a modelling study on the management of patients with OAB who were >/=18 years of age, and had urge or mixed incontinence with a primary-urge component. The study was performed from the perspective of payers (i.e. the National Health Service [NHS] in the UK, Social Security in France and the Sick Funds in Austria) and patients.

METHODS

Clinical outcomes attributable to managing OAB were obtained from the published literature, and resource utilisation estimates were derived from a panel of clinicians. Using decision analytical techniques, three decision models were constructed depicting the management of OAB with CR oxybutynin, IR oxybutynin and tolterodine over 6 months in the UK, France and Austria. The models were used to estimate the cost effectiveness of CR oxybutynin relative to the other two anticholinergic drugs in each of the three countries and the expected direct patient costs and indirect societal costs (at 2000/2001 prices).

MAIN OUTCOME MEASURES AND RESULTS

Starting OAB treatment with CR oxybutynin instead of either IR oxybutynin or tolterodine in the UK and Austria was found to be a potentially dominant strategy, since it improves clinical outcome at a lower cost, from the payers' perspective. In France, starting OAB treatment with CR oxybutynin instead of either the IR formulation or tolterodine was found to be a potentially cost-effective strategy from the payer's perspective. The expected 6-monthly direct costs to patients were euro230, euro720-920 and euro970-1000 in the UK, France and Austria, respectively. In the UK and Austria, these costs were broadly consistent between initial treatments. However, in France, tolterodine-treated patients would be expected to incur 28% more expenditure than patients treated with the other two drugs. Transportation emerged as the primary cost driver, accounting for at least 60% of patients' out-of-pocket expenditure, in all three countries. Irrespective of the initial treatment, patients would be expected to miss 1-2 days of work over 6 months as a result of their OAB. This equates to an expected lost productivity cost of euro84, euro250 and euro98 in the UK, France and Austria, respectively.

CONCLUSION

Starting OAB treatment with CR oxybutynin is expected to be a clinically more effective strategy than starting with either IR oxybutynin or tolterodine, and potentially the most cost-effective strategy in all three countries.

Palliative care treatment patterns and associated costs of healthcare resource use for specific advanced cancer patients in the UK

The purpose of this paper is to identify the treatment patterns and corresponding costs of healthcare resource use associated with palliative care for different types of advanced cancer patients, from the time they started strong opioid treatment until death. This was a modelling study performed from the perspective of the UK's National Health Service (NHS). A data set was created comprising 547 patients in the DIN-Link database who had a Read code for malignant neoplasms with a specific tumour-type diagnosis and who received their first strong opioid between 1 January 1998 and 30 September 2000 and died during that period. Palliative care-related resource utilization data were obtained from the DIN-Link database. Unit costs at 2000/2001 prices were applied to the resource use estimates to determine the mean cost of palliative care from the start of treatment until death. There were significant differences in age between patients with different cancer types and in patients' survival from diagnosis, time to the start of palliative care and duration of palliative care. The mean duration from cancer diagnosis to the start of strong opioid treatment ranged from 0.7 to 5.4 years in patients with lung and breast cancer respectively. Moreover, the length of palliative care ranged from 180 to 372 days in patients with these cancer types respectively. There were also statistically significant differences in resource use between patients with different cancer types, but this reflected, in part, the varying durations of palliative care. Nevertheless, there were also differences in the monthly number of primary care visits reflecting the different number of monthly prescriptions. There was no apparent relationship between the length and corresponding cost of palliative care which ranged from 1816 pounds sterling for colon cancer to 4789 pounds sterling for ovarian cancer. Additionally, on average, only a third of all patients also received 4-hourly morphine as part of their initial strong opioid treatment. The total cost of palliative care varied between cancer type and reflects, at least in part, the distinct clinical features associated with different tumours and the varying lengths of survival following the start of strong opioid treatment. Nevertheless, no apparent relationship was found between length of palliative care and corresponding costs. This analysis provides data on palliative care resource use for a variety of cancers and could provide useful input when planning local healthcare strategies and building service commissioning models.

Cost implications of post-surgical morbidity following blood transfusion in cancer patients undergoing elective colorectal resection: an evaluation in the US hospital setting

OBJECTIVE

To estimate the cost implications of blood transfusions and related surgical site infections (SSIs) in cancer patients undergoing elective colorectal resection in the hospital setting in the United States (US).

STUDY DESIGN

A modelling study was performed from the perspective of the hospital sector, based on published clinical outcomes from a study in Taiwan involving 2809 cancer patients who underwent elective colorectal resection using laparotomy and American treatment patterns.

METHODS

Data on resource use were retrieved from published literature and from two American hospital centres specialising in colorectal cancer management. Decision analytical modelling was used to estimate the treatment costs and consequences of managing patients undergoing elective colorectal resection with and without blood transfusions.

RESULTS

The expected treatment costs of managing patients who required and did not require a blood transfusion were estimated to be US dollars 19,869 (95% CI: 15 797; 23 150) and US dollars 14,586 (95% CI: 14 263; 14 886) per patient respectively. Expected treatment costs for those patients transfused with 1-3 units and > 3 units of blood were estimated to be US dollars 17,449 and US dollars 22,588 per patient respectively.

CONCLUSION

This is one of the first studies to specifically address the cost implications of postsurgical morbidity following colorectal resection in cancer patients. The cost of managing cancer patients undergoing elective colorectal resection who require a blood transfusion is expected to be 36% more than that of non-transfused patients, largely resulting from the development of SSIs.

Switching asthma patients to a once-daily inhaled steroid improves compliance and reduces healthcare costs

OBJECTIVE

To determine the costs and consequences of switching asthma patients, managed in primary care, from a twice-daily inhaled corticosteroid (ICS), to either a once-daily or another twice-daily ICS.

DESIGN

This was a case-control study based on an interrogation of the General Practice Research Database in the UK, for patients with a Read code of asthma who were managed between 1990 and 2001, and who had received at least two prescriptions for a twice-daily ICS within 12 months, before switching to a once-daily ICS (cases) or another twice-daily ICS (controls). Data on resource use was collected for one year before and after the switch. Patients were stratified according to whether their treatment step had been stepped up, stepped down or remained unchanged.

SETTING

A modelling study performed from the perspective of the UK's National Health Service (NHS).

MAIN OUTCOME MEASURES

Compliance with ICS, and the cost of drug and non-drug resource use, for the year before and after the switch.

RESULTS

Switching patients managed in primary care to a once-daily ICS increased compliance and reduced NHS costs, irrespective of whether patients' treatment had been stepped up or down. Switching patients to another twice-daily ICS increased compliance to a lesser extent, and increased NHS costs. We believe that this paper offers the first documented association between compliance in asthma and NHS management costs.

CONCLUSIONS

Compliance and management costs among patients with asthma managed in primary care appear to be related to both changing treatment and dosing regimen. Within the limitations of our study, the results suggest that patients who are switched to a once-daily ICS rather than another twice-daily preparation are better compliers with their ICS medication. Additionally, patients who become high-compliers after being switched to a once-daily ICS incur lower management costs than patients who become high-compliers after being switched to another twice-daily ICS. These findings should now be investigated further under more controlled conditions.

Modelling the cost implications of using carboxymethylcellulose dressing compared with gauze in the management of surgical wounds healing by secondary intention in the US and UK

OBJECTIVE

To estimate the costs of using carboxymethyl cellulose dressing (CMCD; Aquacel* Hydrofiber) compared to gauze in managing surgical wounds healing by secondary intention in the US and UK.

STUDY DESIGN

This was a modelling study performed from the perspective of payers (i.e. the hospital and community sector in the US and the National Health Service (NHS) in the UK).

METHODS

Clinical outcomes attributable to managing surgical wounds healing by secondary intention with gauze were obtained from the published literature in the English language. There were no published studies on wounds healing by secondary intention with CMCD. Hence, the analysis conservatively assumed that wound healing rates associated with gauze would be the same for CMCD. These data were combined with resource utilisation estimates derived from a panel of clinicians enabling us to perform decision modelling. The models were used to determine the expected direct healthcare costs eight weeks after the surgical wounds were dressed by CMCD or gauze and left to heal by secondary intention in the US and UK.

RESULTS

All wounds are expected to heal within eight weeks, irrespective of dressing. Managing abscesses and other surgical wounds with CMCD instead of gauze in the US is expected to reduce costs by 4% in both wound types (i.e. $247 and $507 respectively) per patient over eight weeks. In the UK, managing abscesses and other surgical wounds with CMCD instead of gauze is expected to reduce costs by 30% (574 pounds) and 12% (581 pounds) respectively per patient over eight weeks. The lower cost of managing CMCD-treated patients is due to decreased nursing costs associated with a lower frequency of CMCD changes compared to gauze dressing changes.

CONCLUSION

Dressing surgical wounds healing by secondary intention with CMCD instead of gauze is expected to lead to a reduction in healthcare costs in both the US and UK. Hence, the purchase price of a dressing is not indicative of the cost effectiveness of a given method of surgical wound care.

A comparison of the resources used in advanced cancer care between two different strong opioids: an analysis of naturalistic practice in the UK

OBJECTIVE

To assess the resource implications of using strong opioids in patients with advanced cancer in the UK, based on naturalistic practice, in order to develop the evidence base supporting better management.

DESIGN AND SETTING

A modelling study performed from the perspective of the UK's National Health Service (NHS). Study participants and interventions: A data set was created from the DIN-link database comprising 986 patients with advanced cancer who were prescribed either 12-hourly sustained release morphine (SR morphine; MST Continuous) ( n = 784) or transdermal fentanyl (Durogesic) (n = 202) as their first strong opioid between 1st January 1998 and 30th September 2000 and died during that period.

METHODS

Palliative care-related resource use data were obtained from the DIN-link database. Unit costs at 2000/2001 prices were applied to the resource use values to determine the mean NHS cost of palliative care from the start of treatment until death.

RESULTS

Patients initially treated with transdermal fentanyl started their strong opioid regime 8.5 years after diagnosis compared to 6.4 years after diagnosis in those who started SR morphine. This equates to an overall survival period from diagnosis of 8.8 years and 7.4 years respectively. Nevertheless, the total NHS cost of palliative care was similar between treatment groups, ranging from a mean 3087-3462 pounds per patient. Hospitalisation accounted for up to 71% of the total cost and opioids accounted for up to a further 17%. Less than one-third of patients received 4-hourly morphine as part of their initial opioid treatment despite UK guidelines recommending that moderate-to-severe pain should always be managed initially with an immediate-release preparation. Additionally, patients who received transdermal fentanyl as part of their initial treatment received significantly more laxative prescriptions than patients who started with SR morphine.

CONCLUSIONS

SR morphine and transdermal fentanyl seem to be used in different situations. The results also confirm previous findings that pain management in cancer patients is often sub-optimal. The low contribution of opioids to the overall costs indicates that this should not be an obstacle to starting this aspect of palliative care earlier in disease progression. This characterisation of the resource implications of using SR morphine and transdermal fentanyl should enable purchasers and providers to optimise the availability of strong opioids for cancer patients on medical, economic and humanitarian grounds.

Cost effectiveness of using carboxymethylcellulose dressing compared with gauze in the management of exuding venous leg ulcers in Germany and the USA

OBJECTIVE

To assess the cost effectiveness of using carboxymethylcellulose dressing (CMCD; Aquacel Hydrofiber) compared to gauze in the management of exuding venous leg ulcers in Germany and the USA.

DESIGN AND SETTING

This was a modelling study performed from the perspective of payers (i.e. the sickness funds in Germany and the community sector in the USA).

METHODS

Clinical outcomes attributable to managing exuding venous leg ulcers were obtained from the published literature in the English language. These data were combined with resource utilisation estimates derived from a panel of clinicians enabling us to construct two decision models depicting the management of venous leg ulcers with CMCD or gauze over 18 weeks in Germany and the USA. The models were used to estimate the cost effectiveness of CMCD compared to gauze in the management of exuding venous leg ulcers in both countries.

MAIN OUTCOME MEASURES AND RESULTS

Starting treatment with CMCD instead of gauze in both Germany and the USA is expected to heal 30% of ulcers within 18 weeks compared to 13% with gauze (p = 0.003). The healthcare cost of starting treatment with CMCD or gauze in Germany is expected to be Euro2020 and Euro 2654 respectively at 18 weeks. Additionally, the healthcare cost of starting treatment with CMCD or gauze in the USA is expected to be $3797 and $5288 respectively at 18 weeks. Hence, using CMCD instead of gauze is expected to increase the probability of healing within 18 weeks by 130% and reduce healthcare costs by at least 24%. The healthcare cost of managing CMCD-treated patients was less than that of gauze-treated patients in both countries due to decreased nursing and physician costs associated with a lower frequency of CMCD dressing changes compared to gauze dressing changes. If it were assumed that treatment with gauze in both countries heals 30% of ulcers within 18 weeks (i.e. is identical to CMCD), then the expected healthcare cost of using gauze would be reduced by only 3% (from Euro2654 to Euro2562 in Germany and from $5288 to $5148 in the USA).

CONCLUSION

Within the limitations of our model, starting management of an exuding venous leg ulcer with CMCD instead of gauze is the cost effective strategy in both Germany and the USA. Moreover, the purchase price of a leg ulcer dressing should not be used as an indication of the cost effectiveness of a given method of care.

Costs and consequences of botulinum toxin type A use. Management of children with cerebral palsy in Germany

This study was a retrospective survey of the management of a cohort of children with cerebral palsy at Seepark Hospital, Germany, who did (cases; n=107) and did not (controls; n=107) receive botulinum toxin injections. Data on healthcare resource use and clinical outcomes over 12 months were collected from the date cases received their first injection and from the date controls were first admitted into hospital. Botulinum toxin use led to an 85% reduction in the number of children requiring surgery. Additionally, controls used significantly more healthcare resources than cases, particularly hospital bed days (69.2+/-34.1 vs. 27.5+/-27.9 days; p <0.0001). The total cost of managing cases and controls was <euro>16,700 and <euro>33,800, respectively. In conclusion, use of botulinum toxin released resources for alternative use during the first year following treatment, without any loss of clinical improvement. However, it is unknown how botulinum toxin affected the need for surgery and associated outcomes in subsequent years.

Interaction between milk yield of Holstein cows in Mexico and the United States

Genotype by environment interaction for milk yield was investigated by analyzing 55,162 mature equivalent, first lactation records of daughters from 1339 Holstein sires in Mexico and 499,401 daughters from 663 Holstein sires in the northeastern US. There were 474 US sires in common. Herd-year standard deviation was used to define non-overlapping high (> or = 1600 kg) and low (< or = 1300 kg) Mexican environments and a low (< or = 1025 kg) US environment. Variance components across Mexican environments were about 40% less than those of the US environment. Genetic correlation coefficients between milk yield in various Mexican environments and all US environments ranged from 0.60 to 0.71 and were different from unity (P < 0.001). Genetic correlation coefficients with low environment in the US ranged between 0.69 and 0.93; the largest correlation was between the low US and high Mexico environments. Both reductions in the size of genetic variance in Mexican environments relative to the US and genetic correlation coefficients less than unity were indicative of genotype by environment interaction. A significant rank change in estimated breeding values (EBV) of sires in Mexican environments relative to the US was another indicator of genotype of EBV of a sire estimated from daughters performances in low and high environments in Mexico were 0.46 and 0.62 against EBV of sires estimated from all data in the US. Against EBV estimated from the low environment in the US they were 0.57 and 0.83. The US low environment was a better predictor of performance in Mexican environments.

Evolutionary instability of the major histocompatibility complex class I loci in New World primates

Homologues of the human major histocompatibility complex (MHC) HLA-A, -B, -E, -F, and -G loci are present in all the Catarrhini (Old World primates, apes, and humans), and some of their allelic lineages have survived several speciation events. Analysis of 26 MHC class I cDNAs from seven different genera of New World primates revealed that the Callitrichinae (tamarins and marmosets) are an exception to these rules of MHC stability. In gene trees of primate MHC class I genes, sequences from the Callitrichinae cluster in a genus-specific fashion, whereas in the other genera of New World primates, as in the Catarrhini, they cluster in a transgeneric way. The genus-specific clustering of the Callitrichinae cDNAs indicates that there is no orthology between MHC class I loci in genera of this phyletic group. Additionally, the Callitrichinae genera exhibit limited variability of their MHC class I genes, in contrast to the high variability displayed by all other primates. Each Callitrichinae genus, therefore, expresses its own set of MHC class I genes, suggesting that an unusually high rate of turnover of loci occurs in this subfamily. The limited variability of MHC class I genes in the Callitrichinae is likely the result of the recent origin of these loci.

[Compliance with and abandonment of immunotherapy]

The charts of 247 allergic patients (all ages) who were receiving immunotherapy were studied retrospectively. They belong to a private setting at the city of Santa Ana Chiautempan, Tlax (Mexico). We looked at whether they were compliant or noncompliance. Compliance was considered as those who did not stop immunotherapy during a 18-month period, and shorter periods s noncompliance. One hundred and fifty two (62%) were compliant and 95 (38%) were not. Noncompliance causes were: 29 patients felt better soon, 19 claimed high costs, 8 changed to alternative medicine. 6 felt worse because of immunotherapy, 6 moved to other cities, 2 preferred other allergists and 25 did not answer the questionnaire. Forty six per cent stopped during the first 2 to 6 months and 56% within 8 and 14 with a median of 5.4. Eighty per cent from those who were compliant claimed they felt much better and 18% only slightly better. The average length-compliance was 29.7 months.

[Prick tests for histamine and cow milk in children]

Three hundred and one children were evaluated in six different rural areas in Tlaxcala, State (México). Through skin prick tests which included histamine, glycerine, cow's milk antigen and a drop fulfill a registration form including: personal data; personal and family atopic background; degree and frequency of gastrointestinal, respiratory and cutaneous diseases, as well as the child temperament. Besides, feeding history (length and type of breast-feeding). Six cases were found positive to cow's milk antigen (1.9%) by Prick test but none of them had showed signology related to (83%) were breast-fed at least for the first month of life. Histamine wheal size increased progressively up to eight months of age and reached a plateau.

Role of nitric oxide and prostaglandins in the regulation of blood pressure in conscious rats

The present study was designed to investigate the possible role of endothelium-derived vasodilators, nitric oxide and prostaglandins, in the regulation of blood pressure during the presence and absence of the major pressor systems. Conscious rats were infused with a cocktail of inhibitors of the sympathetic nervous system, renin-angiotensin system, and V1 vascular receptor to vasopressin (achieved with hexamethonium, captopril, phentolamine, propranolol, and the V1 vasopressin (AVP) antagonist des-(CH2)5Tyr(Me)-AVP). The cocktail of vasoconstrictor inhibitors induced a marked fall of mean arterial pressure (MAP) from 109 +/- 2 to 52 +/- 2 mmHg (1 mmHg = 133.3 Pa) (n = 24). In animals with blockade, the specific inhibitor of nitric oxide synthesis, NG-nitro-L-arginine methyl ester (L-NAME), induced a significant increase of MAP from 51 +/- 1 to 84 +/- 2 mmHg (n = 6). In the presence of indomethacin, a cyclooxygenase inhibitor, the pressor response to L-NAME was from 52 +/- 2 to 126 +/- 4 mmHg (n = 6). Neither indomethacin (n = 6) nor vehicle (n = 6) alone altered MAP. In intact animals without blockade, L-NAME caused a similar increase of MAP when it was injected alone (from 107 +/- 3 to 144 +/- 4 mmHg, n = 7) or with indomethacin (from 113 +/- 3 to 144 +/- 3, n = 6). Indomethacin alone (n = 8) did not change MAP. In conclusion, in the absence of the major pressor systems, the pressor effect of the inhibition of the production of endogenous nitric oxide and vasodilator prostanoid synthesis appears to be synergistic. These results suggest that these two endogenous vasodilators are involved in the maintenance of blood pressure.

[Is it possible to improve psychiatric care through the referral process?]

OBJECTIVE

To evaluate the quality of referral from Primary Care to Mental Health and its relationship to the illness referred.

DESIGN

A descriptive retrospective study over 4 years on the quality of the process.

SETTING

Mental Health Centre II in the Autonomous Community of Murcia.

PATIENTS

209 patients referred by three Primary Care teams.

MEASUREMENTS AND MAIN RESULTS

91.4% of patients (C.I. 95%: 100%, 81.1%) were accepted with a referral report. 97.9% (C.I. 95%: 100%, 87.8%) presented a reason for psychiatric consultation. The report included the clinical history of the illness in 58.1% of cases (C.I. 95%: 70.3%, 45.9%); a diagnostic opinion was given in 79.6% (C.I. 95%: 91.1%, 68%); and 37.2% (C.I. 95%: 49.3%, 25%) were referred with a request for a specific consultation. 68.4% of the referrals (C.I. 95%: 81.8%, 54.9%) coincided with the Mental Health diagnosis. It was observed that among the most commonly referred pathologies: anxiety disorders (31.6%), affective (28.8%), personality (7.7%), psychotic (5.3%), and adaptive disorders (5.3%); diagnoses were commonly made for affective or anxiety disorders (p < 0.0001); the specific cause of referral of anxiety disorders was recorded (p < 0.01); and in cases of psychotic and personality disorders, the diagnoses did not coincide (p < 0.001).

CONCLUSIONS

Referral to Mental Health can be improved, fundamentally by sending a report which includes the clinical history and the reason for referral. It is common to express a diagnostic opinion on affective and anxiety disorders, to note a specific reason for referral in the case of anxiety disorders and not to specify personality and psychotic disorders.

[Salmonella enteritidis multifocal infection of the central nervous system. Efficacy of new cephalosporins]

Focal central nervous system infections, as abscess and empyema, due to Salmonella species are unusual. Even more unusual is the association of cerebral abscess, subdural empyema and epidural abscess we report in the present work. This infection appeared in our patient soon after a brain astrocytoma removal and was treated with cefotaxime and gentamicin during three weeks. In spite of documented genus susceptibility to the drugs the infection relapsed in few days. It was definitely cured with ceftazidime alone for six weeks. Third-generation cephalosporins are good alternatives in uncommon infections and specially in central nervous system salmonellosis, as resistances of this genus to classical drugs are lately increasing.

N-acetyl-L-cysteine potentiates depressor response to captopril and enalaprilat in SHRs

Recently, in vivo and in vitro studies have implicated nitric oxide as a mediator of the vascular effects of angiotensin-converting enzyme inhibitors (ACEIs). In the present study we hypothesized that N-acetyl-L-cysteine (NAC), by increasing the availability of reduced sulfhydryl groups, would enhance the antihypertensive response to the ACEIs captopril and enalaprilat by a mechanism dependent on nitric oxide. The experiments were performed on instrumented, indomethacin-pretreated, awake spontaneously hypertensive rats (SHRs). Thirty minutes after a bolus of captopril (10 mg/kg iv) was administered, blood pressure decreased from 167 +/- 5 to 147 +/- 6 mmHg (n = 8). The pretreatment with the donor of thiol groups NAC (300 mg/kg iv) potentiated the depressor response to captopril because blood pressure decreased from 172 +/- 3 to 139 +/- 4 mmHg (n = 6). At the dose of 60 micrograms/kg iv, the ACEI enalaprilat did not acutely modify the blood pressure of SHRs (from 172 +/- 5 to 167 +/- 4 mmHg; n = 6). However, when the SHRs were pretreated with NAC, the same dose of enalaprilat significantly reduced blood pressure from 176 +/- 5 to 151 +/- 5 mmHg (n = 6). This potentiation of the depressor response to ACEIs, due to NAC, was not observed when SHRs were pretreated with the nitric oxide inhibitor NG-nitro-L-arginine methyl ester (L-NAME; 50 micrograms.kg-1.min-1 iv). The results of this study suggest that NAC, a donor of sulfhydryl groups, potentiates the antihypertensive response to captopril and enalaprilat in SHR by a nitric oxide-dependent mechanism.

Indomethacin does not modify the role of nitric oxide on blood pressure regulation of SHR

1. The endothelium-dependent relaxation is impaired in spontaneously hypertensive rats (SHR) by the release of a vasoconstrictor prostanoid. We evaluated whether such a vasoconstrictor prostanoid is masking the vasodilatation induced by nitric oxide (NO). 2. For this we observed, in SHR, whether indomethacin (INDO) modified both the pressor response to the inhibition of NO biosynthesis with L-nitro-arginine methyl ester (L-NAME) and the acute hypotensive response to acetylcholine. 3. INDO did not modify basal mean arterial pressure (MAP), either the pressor response to L-NAME, or the depressor response to acetylcholine. 4. It shows that, in awake SHR, a vasoconstrictor prostanoid, did not seem to affect the acute regulatory function of NO on MAP.

[Family planning: an evaluation of the program at a health center (1986-1990)]

OBJECTIVE

To gain dome idea of the characteristics of the population attended at a Family Planning Clinic (FPC) in a Health Centre, attempting to find the coverage and performance of the Clinic.

DESIGN

Retrospective descriptive study, which analysed 403 cases between July 1986 and December 1990. SITE. Family Planning Clinic in the "Huerta de la Reina" Health Centre.

PATIENTS AND OTHERS PARTICIPANTS

Women of child-bearing age who requested a consultation during the period of the study.

MAIN MEASUREMENTS AND RESULTS

A uni/bivariate analysis of the studies was carried out. Coverage of 16.3% of the population of child-bearing age, with 69.5% of the women being under 29, was attained. The most frequent motive for a consultation was advice on methods of contraception. Oral contraception (65.0%) was the most common form prescribed. 27.1% of those attending consultation were referred to the second level. Attendance at periodic check-ups was very low.

Cost-benefit evaluation of on-farm milk progesterone testing to monitor return to cyclicity and to classify ovarian cysts

The effect of using on-farm milk progesterone testing to monitor return to cyclicity after parturition and to classify correctly and to treat cystic cows was evaluated using modeling and simulation. The test was evaluated assuming low and high accuracies of progesterone measurement, first breeding policy of 40 d, average estrus detection rate of 55%, and an average fertility rate of 55%. Three testing schemes (starting milk progesterone testing on d 30, 40, or 50 after parturition) were compared against a control to evaluate the effect of monitoring return to cyclicity on cows' reproductive and economic performance. For this purpose, the use of the test was an economically justifiable management intervention. Starting to test on d 30 after parturition was the most effective scheme, reducing days open by 18 d, replacement rate by 2.4%, and increasing net return per cow per year by $11. Starting to test on d 50 postpartum was not economically justifiable. Accuracy of the test, within the range used in this study, was unimportant. Testing was most profitable in herds with low fertility and low efficiency of estrus detection. The use of the test to classify follicular and luteal cysts and to select the appropriate therapy was not economically justifiable because of the low proportion of cystic cows and the high variation in response to therapy.

[Factors affecting the duration of maternal breast-feeding in a cohort of urban mothers studied longitudinally]

A prospective study on the incidence and duration of breastfeeding in a cohort of urban women of the city of Tlaxcala was carried-out in a private pediatric clinic from January, 1983 to December, 1987. In a total of 547 women studied, breastfeeding had a median of three months, and only 5% of the children continued to be breastfed at one year of age. Family tradition of breastfeeding, late introduction of solid foods and/or whole milk and less formal education of the mother were factors related with breastfeeding beyond three months. About 70% of the mothers weaned their children claiming a rejection of the breast-milk by the child, a lack of sufficient quantity to fulfill the child's needs or because of their work outside the home.