Pharmacogeriatrics

The role of sex work laws and stigmas in increasing HIV risks among sex workers

Globally HIV incidence is slowing, however HIV epidemics among sex workers are stable or increasing in many settings. While laws governing sex work are considered structural determinants of HIV, individual-level data assessing this relationship are limited. In this study, individual-level data are used to assess the relationships of sex work laws and stigmas in increasing HIV risk among female sex workers, and examine the mechanisms by which stigma affects HIV across diverse legal contexts in countries across sub-Saharan Africa. Interviewer-administered socio-behavioral questionnaires and biological testing were conducted with 7259 female sex workers between 2011-2018 across 10 sub-Saharan African countries. These data suggest that increasingly punitive and non-protective laws are associated with prevalent HIV infection and that stigmas and sex work laws may synergistically increase HIV risks. Taken together, these data highlight the fundamental role of evidence-based and human-rights affirming policies towards sex work as part of an effective HIV response.

Delivering domiciliary pharmaceutical care from a health centre pharmacy

Aim

To develop and administer a pharmacist domiciliary visiting programme from a community pharmacy based in a health centre.

Design

Prospective cohort with peer professional intervention assessment and patient feedback questionnaires.

Subjects and setting

Total general practitioner surgery list (4,922 patients) in an urban residential area. Candidates were defined by three inclusion criteria: 65 years or older taking five or more repeat medicines (polypharmacy); any age plus polypharmacy plus significant disablement; 80 years or older taking three or more specified medications on repeat prescription.

Outcome measures

Interventions made during a programme of three visits for each patient; peer assessment of impact on patient care and cost by the three surgery GPs and three clinical pharmacists; patients' perceived worth of the service; cost of the service.

Results

One hundred patients (2 per cent) were visited over a period of six months; 74 completed the three-visit programme that involved a total of 256 visits. There were 160 interventions classified as: medicines management issues (88), health beliefs and concordance (41) or therapeutic problems, including adverse effects (31). Nineteen patients required specific and detailed collaboration with the patient's GP. There was good agreement on the utility of the pharmacist's interventions at this level with only four negative assessments out of a possible 114 (3.5 per cent). The programme was well received by patients. Talking to a pharmacist (as opposed to another health care professional) about their medicines was important to 70 of 74 patients. Sixty-one described their reaction to the visiting programme using one of three positive adjectives, “relieved,” “reassured” or “grateful”. Based on this cohort, the estimated costs to the pharmacy were £5,000 per annum, equivalent to 33 working days. Cost savings based on outcomes were not estimated.

Conclusions

This study demonstrated the feasibility of identifying candidates for domiciliary care from surgery records using carefully selected inclusion criteria. This is likely to encompass between 2 and 3 per cent of a surgery population. The visiting programme, which was well received by patients, had a favourable effect on patient care in the majority of the cohort and a very important impact in a minority (19 per cent). This success required the commitment of all members of the health centre team. It benefited from the proximity of the visiting pharmacist to medical records and prescribers.

Pharmacokinetic and pharmacodynamic alterations in the geriatric patient

Adverse drug events (ADEs) are all too common in older patients. Although there are multiple causes for the ADEs in the elderly, alterations in pharmacokinetics (PK) and pharmacodynamics (PD) are frequent culprits. These alterations in PK and PD may be part of the normal aging process. Older patients often develop significant drug-related problems when alterations in PK and PD are not appropriately accounted for in prescribing and monitoring of medications. Clinically, the most significant PK changes that occur in aging are renal elimination and metabolism of drugs. In general, renal function declines with aging, necessitating dosage adjustments for drugs with renal-elimination pathways. The ability of the liver to metabolize certain drugs may also decline as a consequence of the aging process. From a PD standpoint, exaggerated responses are frequent, and often it is the side effects of medications that become exaggerated, rather than the therapeutic effects. Drugs affecting the central nervous system are particularly prone to PD alterations. Because of the PK and PD changes, vigilant monitoring of both therapeutic and adverse effects is mandatory in older patients. Based on PK and PD differences between middle-aged and elderly patients, there are certain medications that should almost always be avoided in older people. In addition, because older people tend to use more medications, the incidence of drug-drug interactions becomes more prevalent. Most of the drug-drug interactions that adversely impact older people involve both PK and PD mechanisms. Pharmacists and all prescribers must have a sound understanding of PK and PD effects of medications used in older people to provide optimal care and avoid preventable drug-related problems.

Unique aspects of antimicrobial use in older adults

Elderly persons consume a significant proportion of health care resources. Antimicrobials are just one class among many pharmaceuticals that are prescribed more frequently to elderly patients than to younger patients. There are unique aspects of antimicrobial use in elderly persons that make prescribing complicated and monitoring unpredictable. Physiologic changes associated with aging result in altered pharmacokinetics, and accurate estimates of renal function cannot be made with standard methods. Together, these qualities make antimicrobial dosing difficult. Because of a higher prevalence of other chronic diseases, there is a greater propensity for polypharmacy and a resulting risk of an adverse event or a significant drug interaction. Lastly, irrespective of altered pharmacokinetics, adverse effects of many antimicrobials are more common in elderly persons, which introduces an added dimension to ensuring safety with antimicrobial therapy.

Understanding and preventing drug interactions in elderly patients

The elderly consume a disproportionate amount of prescription and nonprescription medications. Alterations in physiology, polypharmacy, multiple prescribers, and other factors place the elderly population at risk of developing clinically significant drug-drug interactions. The incidence of potential drug-drug interactions increases with increased drug use and are responsible for numerous emergency room and physician visits. Drug interactions have been shown to cause a decline in functional abilities in older people. Drugs can interact to alter the absorption, distribution, metabolism, or excretion of a drug or interact in a synergistic or antagonist fashion altering their pharmacodynamics. Drug interactions are often clinically unrecognized and responsible for increased morbidity in elderly patients. Prudent use of medications and vigilant drug monitoring are essential to avoid drug-drug interactions.

Successful orchestration of antiparkinsonian pharmacotherapy

As is true with the orchestration of essentially all forms of pharmacotherapy, the overall quality of therapy should not be judged as a simple binary function (it is either good or bad). Rather, it should be judged along a continuum, spanning adequate through excellent and peaking at truly elegant, where two or more disease states are optimally managed with a single, simple drug. Because the difference between adequate and elegant therapy often depends on fine-tuning the drug choice, dosage, and route of administration, it is no surprise that pharmacists are often intimately involved in many highly successful specialty clinics, including Parkinson's disease clinics.

High-risk drugs in the elderly population

Drug therapy in elderly patients is affected by age-related changes in distribution and elimination and is further complicated by the increased sensitivity aged persons have to many of the effects of medications. Medications are often necessary in the elderly population, but care should be made to properly monitor these patients, especially those taking multiple drugs. Nurses, who are at the front lines of health care in all areas of practice, should be aware of drugs that may be high risk for use in the elderly and monitor these patients carefully for signs and symptoms of toxicity.

Pharmacokinetics and bioavailability of flucloxacillin in elderly hospitalized patients

The pharmacokinetics and oral bioavailability of flucloxacillin were studied in five female and two male patients (age 68-87 yr) who had been hospitalized for orthopedic surgeries. A single dose of intravenous or oral flucloxacillin sodium (500 mg) was administered in random order on different occasions separated by at least 2 days. Blood and urine samples were taken up to 24 hours after drug administration and levels of flucloxacillin and 5-hydroxymethylflucloxacillin (5-HMF), a major metabolite, were measured by high-performance liquid chromatography. Flucloxacillin elimination, but not oral absorption, was reduced in the elderly, compared with data from young healthy subjects reported elsewhere. Total clearance, renal clearance, and volume of distribution were 0.083 +/- 0.013 L/kg/hr, 0.038 +/- 0.01 L/kg/hr, and 0.184 +/- 0.034 L/kg, respectively. Regression of flucloxacillin renal clearance (Clr) on estimated creatine clearance (CLcr) gave the relationship: Clr = 0.755 (CLcr) + 10.6 (r = 0.91; P = 0.004). Terminal half-lives for flucloxacillin and 5-HMF were 2.21 +/- 0.51 hr and 3.0 +/- 0.75 hr, respectively after intravenous administration. Flucloxacillin was absorbed rapidly after oral administration with a mean absorption time of 0.95 +/- 0.34 hr, and time to reach peak concentration of 1.20 +/- 0.29 hr. The absolute bioavailability of flucloxacillin from capsules was 54.4 +/- 18.8%.

Poisoning in the elderly: characterization of exposures reported to a poison control center

OBJECTIVE

To determine the incidence of poison center calls involving the elderly, characterize these poisonings, and compare them with poisonings that occur in people younger than 60 years of age.

DESIGN

Concurrent, observational survey.

SETTING

The Virginia Poison Center in Richmond, Virginia.

PARTICIPANTS

All persons 60 years of age and older who were involved in a poison exposure reported to the Virginia Poison Center from October 1, 1991 through March 31, 1992.

MEASUREMENTS

Incidence, type, route, location, management site, medical outcome of exposures and reasons for these exposures.

RESULTS

Exposures in persons 60 years of age and older accounted for 2.3% of all poison center calls during the 6-month study period. These calls were most likely to involve women who unintentionally ingested extra doses of medications. The majority of these exposures occurred in the home and resulted in either no effect or minor effects. For those exposures that necessitated an emergency room visit, elderly persons were more likely to be admitted to the hospital than younger persons (P < 0.05).

CONCLUSIONS

The majority of poisonings that occur in persons 60 years of age and older are unintentional and may be amenable to poison prevention education.

Adverse effects of antidepressants in the elderly

Depression is a common problem in old age and the use of antidepressant drugs is particularly prevalent among elderly patients. Limited data suggest that dose requirements may be lower in the elderly because of age-related changes in pharmacokinetics and perhaps also in sensitivity. The side effect profiles of the various antidepressants are reviewed with regard to their potential to cause specific problems in the older patients. Anticholinergic actions, orthostatic hypotension and sedative effects warrant particular care in the elderly.

Iatrogenesis in the elderly. Drug-related problems

Drug reactions are generally related to the influence of age, toxicity, side effects, immunologic reactions, idiosyncratic reactions, drug-drug interactions, and drug-disease interactions. In addition to age-related changes, the elderly are susceptible to the incidence of adverse drug reactions because of polypharmacy, incorrect self-administration of drugs, omission of drugs, taking another's prescriptions, use of over-the-counter drugs, and medication errors by health-care personnel. To prevent or predict adverse drug reactions, the gerontologic nurse can obtain thorough drug histories, educate clients and health-care providers, use nursing measures to alleviate symptoms, and be astute for the potential for problems through drug review.

A team approach to reduce antibiotic costs

After partial success in reducing antibiotic drug costs by traditional methods (i.e., closed formulary, use of generic drugs, retrospective drug usage review, continuing education), a study of a new "team approach" was implemented. The study involved a clinical pharmacist and physicians working together to select the most appropriate antibiotic therapy. The clinical pharmacist reviewed the culture and sensitivity data and the pattern of infectious disease over the six-month period prior to the initiation of the study and prepared a list of the most appropriate antibiotics based on clinical efficacy and cost effectiveness. He then joined the physicians on morning rounds to monitor therapy and help in the selection of the most appropriate drug regimen. At the end of the study period, antibiotic cost savings of 58.6 percent were achieved.

Protein binding: what does it mean?

Protein binding can enhance or detract from a drug's performance. As a general rule, agents that are minimally protein bound penetrate tissue better than those that are highly bound, but they are excreted much faster. Among drugs that are less than 80-85 percent protein bound, differences appear to be of slight clinical importance. Agents that are highly protein bound may, however, differ markedly from those that are minimally bound in terms of tissue penetration and half-life. Drugs may bind to a wide variety of plasma proteins, including albumin. If the percentage of protein-bound drug is greater when measured in human blood than in a simple albumin solution, the clinician should suspect that the agent may be bound in vivo to one of these "minority" plasma proteins. The concentration of several plasma proteins can be altered by many factors, including stress, surgery, liver or kidney dysfunction, and pregnancy. In such circumstances, free drug concentrations are a more accurate index of clinical effect than are total concentrations. Formulary committees must grasp the clinical significance of qualitative and quantitative differences in protein binding when evaluating competing agents.

Research in Long-term Care Facilities

Clinical research in geriatrics, to date, has focused on the ambulatory and acutely ill patient populations. However, the unique host, disease, and environmental factors common to the nursing home resident and facility underline the need to study drug use and response in the long-term care facility. Five specific areas require investigation: efficacy, safety, dosages, utilization, and cost. To adequately study these topics, interdisciplinary research teams may use methodologies from various backgrounds, including the biologic, agricultural, epidemiologic, economic, and ethnographic research traditions. Even with the numerous methodologies available, significant procedural and design issues confront the development and performance of long-term care research. While procedural problems usually involve legal and administrative issues, methodologic concerns often stem from the need to deal with multiple confounding variables or the limitations of available research tools and clinical data bases. Continued improvement in the existing quality-of-life and functional assessment instruments as well as the development of computerized nursing home data bases will enhance clinical research in the long-term care facility.

Interactions of non-steroidal anti-inflammatory drugs

As NSAIDs are commonly used in patients receiving concomitant drug therapy, there is a risk of clinically significant drug interactions. Important interactions with NSAIDs involve one or both of two major mechanisms: pharmacokinetic (e.g. lithium, phenytoin and barbiturates) and pharmacodynamic (e.g. antihypertensive agents, diuretics). Prescription of a NSAID should be preceded by a careful evaluation of any coexisting pathology (such as renal dysfunction or hypertension) or concurrent drug therapy (such as anticonvulsant or anticoagulant agents) which may predispose a patient to the development of an interaction with potentially severe effects.

Clinical research in the elderly: ethical and methodological considerations

Clinically oriented research in the elderly is of growing interest because of increasing numbers of older persons, the relative lack of research data with this population, and recent Food and Drug Administration mandates to study drugs in the elderly. Studies of young, healthy persons cannot necessarily be extrapolated to the elderly due to changes associated with aging and the increased number of concomitant disease states and medications. Subject recruitment may be more time consuming in finding subjects with the appropriate inclusion criteria and lack of exclusion criteria who are willing to participate. Additional concern must be placed on protecting the subject's rights while allowing autonomous decision making. Likewise, protocols may need to be flexible enough to include persons with concomitant disease and medications.