Adaptations for bipedal walking: Musculoskeletal structure and three-dimensional joint mechanics of humans and bipedal chimpanzees (Pan troglodytes).

Humans are unique among apes and other primates in the musculoskeletal design of their lower back, pelvis, and lower limbs. Here, we describe the three-dimensional ground reaction forces and lower/hindlimb joint mechanics of human and bipedal chimpanzees walking over a full stride and test whether: 1) the estimated limb joint work and power during the stance phase, especially the single-support period, is lower in humans than bipedal chimpanzees, 2) the limb joint work and power required for limb swing is lower in humans than in bipedal chimpanzees, and 3) the estimated total mechanical power during walking, accounting for the storage of passive elastic strain energy in humans, is lower in humans than in bipedal chimpanzees. Humans and bipedal chimpanzees were compared at matched dimensionless and dimensional velocities. Our results indicate that humans walk with significantly less work and power output in the first double-support period and the single-support period of stance, but markedly exceed chimpanzees in the second double-support period (i.e., push-off). Humans generate less work and power in limb swing, although the species difference in limb swing power was not statistically significant. We estimated that total mechanical positive 'muscle fiber' work and power were 46.9% and 35.8% lower, respectively, in humans than in bipedal chimpanzees at matched dimensionless speeds. This is due in part to mechanisms for the storage and release of elastic energy at the ankle and hip in humans. Furthermore, these results indicate distinct 'heel strike' and 'lateral balance' mechanics in humans and bipedal chimpanzees and suggest a greater dissipation of mechanical energy through soft tissue deformations in humans. Together, our results document important differences between human and bipedal chimpanzee walking mechanics over a full stride, permitting a more comprehensive understanding of the mechanics and energetics of chimpanzee bipedalism and the evolution of hominin walking.

The loss of the 'pelvic step' in human evolution.

Human bipedalism entails relatively short strides compared with facultatively bipedal primates. Unique non-sagittal-plane motions associated with bipedalism may account for part of this discrepancy. Pelvic rotation anteriorly translates the hip, contributing to bipedal stride length (i.e. the 'pelvic step'). Facultative bipedalism in non-human primates entails much larger pelvic rotation than in humans, suggesting that a larger pelvic step may contribute to their relatively longer strides. We collected data on the pelvic step in bipedal chimpanzees and over a wide speed range of human walking. At matched dimensionless speeds, humans have 26.7% shorter dimensionless strides, and a pelvic step 5.4 times smaller than bipedal chimpanzees. Differences in pelvic rotation explain 31.8% of the difference in dimensionless stride length between the two species. We suggest that relative stride lengths and the pelvic step have been significantly reduced throughout the course of hominin evolution.

Chimpanzee super strength and human skeletal muscle evolution.

Since at least the 1920s, it has been reported that common chimpanzees (Pan troglodytes) differ from humans in being capable of exceptional feats of "super strength," both in the wild and in captive environments. A mix of anecdotal and more controlled studies provides some support for this view; however, a critical review of available data suggests that chimpanzee mass-specific muscular performance is a more modest 1.5 times greater than humans on average. Hypotheses for the muscular basis of this performance differential have included greater isometric force-generating capabilities, faster maximum shortening velocities, and/or a difference in myosin heavy chain (MHC) isoform content in chimpanzee relative to human skeletal muscle. Here, we show that chimpanzee muscle is similar to human muscle in its single-fiber contractile properties, but exhibits a much higher fraction of MHC II isoforms. Unlike humans, chimpanzee muscle is composed of ∼67% fast-twitch fibers (MHC IIa+IId). Computer simulations of species-specific whole-muscle models indicate that maximum dynamic force and power output is 1.35 times higher in a chimpanzee muscle than a human muscle of similar size. Thus, the superior mass-specific muscular performance of chimpanzees does not stem from differences in isometric force-generating capabilities or maximum shortening velocities-as has long been suggested-but rather is due in part to differences in MHC isoform content and fiber length. We propose that the hominin lineage experienced a decline in maximum dynamic force and power output during the past 7-8 million years in response to selection for repetitive, low-cost contractile behavior.

A Multicenter Comparison of Complementary and Alternative Medicine (CAM) Discussions in Oncology Care: The Role of Time, Patient-Centeredness, and Practice Context.

BACKGROUND: Little is known about how complementary and alternative medicine (CAM) is discussed in cancer care across varied settings in the U.S. METHODS: In two practices affiliated with one academic medical center in southern California (SoCal), and one in the upper Midwest (UM), we audio-recorded patient-clinician interactions in medical oncology outpatient practices. We counted the frequency and duration of CAM-related conversations. We coded recordings using the Roter Interaction Analysis System. We used chi-square tests for bivariate analysis of categorical variables and generalized linear models for continuous variables to examine associations between dialogue characteristics, practice setting, and population characteristics with the occurrence of CAM discussion in each setting followed by multivariate models adjusting for clinician clustering. RESULTS: Sixty-one clinicians and 529 patients participated. Sixty-two of 529 (12%) interactions included CAM discussions, with significantly more observed in the SoCal university practice than in the other settings. Visits that included CAM were on average 6 minutes longer, with CAM content lasting an average of 78 seconds. In bivariate tests of association, conversations containing CAM included more psychosocial statements from both clinicians and patients, higher patient-centeredness, more positive patient and clinician affect, and greater patient engagement. In a multivariable model including significant bivariate terms, conversations containing CAM were independently associated with higher patient-centeredness, slightly longer visits, and being at the SoCal university site. CONCLUSION: The frequency of CAM-related discussion in oncology varied substantially across sites. Visits that included CAM discussion were longer and more patient centered. IMPLICATIONS FOR PRACTICE: The Institute of Medicine and the American Society of Clinical Oncology have called for more open discussions of complementary and alternative medicine (CAM). But little is known about the role population characteristics and care contexts may play in the frequency and nature of those discussions. The present data characterizing actual conversations in practice complements a much larger literature based on patient and clinician self-report about CAM disclosure and use. It was found that CAM discussions in academic oncology visits varied significantly by practice context, that the majority were initiated by the patient, and that they may occur more when visit time exists for lifestyle, self-care, and psychosocial concerns.

Great ape thorax and shoulder configuration-An adaptation for arboreality or knuckle-walking?

Great apes exhibit a suite of morphological traits of the shoulder and upper thorax that have traditionally been linked to orthograde arborealism. Recently it has been proposed that these traits are instead adaptations for knuckle-walking, and more broadly, that knuckle-walking itself is an adaptation for shock absorption during terrestriality. Here we test several tenets of these hypotheses using kinematic and kinetic data from chimpanzees and macaques, and electromyographic data of shoulder muscle activity in chimpanzees. We collected 3D kinematic data to quantify motion of the acromion and trunk during quadrupedalism and vertical climbing in chimpanzees as well as ground reaction forces to investigate the presence and magnitude of impact transient forces during terrestrial locomotion in chimpanzees and macaques. We also investigated patterns of recruitment of select forelimb musculature (triceps brachii and serratus anterior) using previously collected data in chimpanzees to determine whether these muscles may function to absorb impact transient forces. We found that the acromion is significantly more elevated in vertical climbing than during knuckle-walking, while dorsoventral ranges and magnitudes of motion were similar between gaits. Ground reaction forces indicate that only a minority of strides in either chimpanzees or macaques have transient forces and, when present, these transient forces as well as loading rates are small. Electromyographic results show that activity of the triceps brachii may facilitate energy absorption while serratus anterior likely functions to support the trunk, as in other primates. Our data suggest there is little to no evidence supporting recent hypotheses that the African ape upper thorax and shoulder configuration is an adaptation for knuckle-walking, or more broadly, that knuckle-walking exists as an adaptation to absorb impact shock during terrestriality. We do however find some evidence that shoulder configuration allows greater scapular elevation in chimpanzees during arboreal behaviors (e.g., vertical climbing).

Family Conferences in the Neonatal ICU: Observation of Communication Dynamics and Contributions.

OBJECTIVES: Clinicians in the neonatal ICU must engage in clear and compassionate communication with families. Empirical, observational studies of neonatal ICU family conferences are needed to develop counseling best practices and to train clinicians in key communication skills. We devised a pilot study to record and analyze how interdisciplinary neonatal ICU clinicians and parents navigate difficult conversations during neonatal ICU family conferences. DESIGN: We prospectively identified and audiotaped a convenience sample of neonatal ICU family conferences about "difficult news." Conversations were analyzed using the Roter interaction analysis system, a quantitative tool for assessing content and quality of patient-provider communication. SETTING: An urban academic children's medical center with a 45-bed level IV neonatal ICU. SUBJECTS: Neonatal ICU parents and clinicians. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We analyzed 19 family conferences that included 31 family members and 23 clinicians. The child's mother was included in all conferences, and a second parent, usually the father, was present in 13 conferences. All but one conference included multiple medical team members. On average, physicians contributed 65% of all dialogue, regardless of who else was present. Over half (56%) of this dialogue involved giving medical information; under 5% of clinician dialogue involved asking questions of the family, and families rarely (5% of dialogue) asked questions. Conversations were longer with the presence of nonphysician clinicians, but this did not increase the amount of dialogue about psychosocial information or increase parent dialogue. CONCLUSIONS: We collected a novel repository of audio-recorded neonatal ICU family meetings that offers insights into discussion content and process. These meetings were heavily focused on biomedical information even when interdisciplinary clinicians were present. Clinicians always talked more than parents, and no one asked many questions. Maximizing the participation of interdisciplinary clinicians in neonatal ICU family meetings may require explicit strategies. Methods to increase family engagement should be targeted.

Rotator cuff muscle size and the interpretation of scapular shape in primates.

Scapular shape variation among primates is widely viewed as being strongly related to locomotor differences. The relative importance of overhead forelimb elevation in the locomotor repertoire of a species, as reflected in muscular leverage for scapular rotation or in the sizes of attachment areas for muscles involved in glenohumeral elevation, has proven to be a useful organizing principle for understanding this variation. While generally successful in sorting primate scapulae into functional groups, the scapulae of some species do not entirely match predictions based on the perceived importance of forelimb elevation. A recent study has shown that scapular fossa sizes in apes are not as accurate predictors of the sizes of the muscles arising from them as has been assumed. To further explore the degree of correspondence between actual and predicted muscle size based on the perceived importance of forelimb elevation, the current study examines the relative sizes of the rotator cuff muscles in a wider sample of primate taxa using published data on muscle mass and cross-sectional area. The results do not support some of the accepted generalizations about the relative sizes of members of the rotator cuff based on measurements of the sizes of scapular fossae. For example, orthograde apes do not display enlarged supraspinatus muscles compared to pronograde monkeys. Differences in assessments of relative muscle size based on mass compared to those based on cross-sectional area suggest that poor correspondence between muscle size predicted from scapular fossa size and actual muscle size may be related to constraints on scapular form associated with muscular leverage for scapular rotation and with scapular position on the thorax.

Distinct functional roles of primate grasping hands and feet during arboreal quadrupedal locomotion.

It has long been thought that quadrupedal primates successfully occupy arboreal environments, in part, by relying on their grasping feet to control balance and propulsion, which frees their hands to test unstable branches and forage. If this interlimb decoupling of function is real, there should be discernible differences in forelimb versus hind limb musculoskeletal control, specifically in how manual and pedal digital flexor muscles are recruited to grasp during arboreal locomotion. New electromyography data from extrinsic flexor muscles in red ruffed lemurs (Varecia rubra) walking on a simulated arboreal substrate reveal that toe flexors are activated at relatively higher levels and for longer durations than finger flexors during stance phase. This demonstrates that the extremities of primates indeed have different functional roles during arboreal locomotion, with the feet emphasizing maintenance of secure grips. When this dichotomous muscle activity pattern between the forelimbs and hind limbs is coupled with other features of primate quadrupedal locomotion, including greater hind limb weight support and the use of diagonal-sequence footfall patterns, a complex suite of biomechanical characters emerges in primates that allow for the co-option of hands toward non-locomotor roles. Early selection for limb functional differentiation in primates probably aided the evolution of fine manipulation capabilities in the hands of bipedal humans.

Three-dimensional kinematics of the pelvis and hind limbs in chimpanzee (Pan troglodytes) and human bipedal walking.

The common chimpanzee (Pan troglodytes) is a facultative biped and our closest living relative. As such, the musculoskeletal anatomies of their pelvis and hind limbs have long provided a comparative context for studies of human and fossil hominin locomotion. Yet, how the chimpanzee pelvis and hind limb actually move during bipedal walking is still not well defined. Here, we describe the three-dimensional (3-D) kinematics of the pelvis, hip, knee and ankle during bipedal walking and compare those values to humans walking at the same dimensionless and dimensional velocities. The stride-to-stride and intraspecific variations in 3-D kinematics were calculated using the adjusted coefficient of multiple correlation. Our results indicate that humans walk with a more stable pelvis than chimpanzees, especially in tilt and rotation. Both species exhibit similar magnitudes of pelvis list, but with segment motion that is opposite in phasing. In the hind limb, chimpanzees walk with a more flexed and abducted limb posture, and substantially exceed humans in the magnitude of hip rotation during a stride. The average stride-to-stride variation in joint and segment motion was greater in chimpanzees than humans, while the intraspecific variation was similar on average. These results demonstrate substantial differences between human and chimpanzee bipedal walking, in both the sagittal and non-sagittal planes. These new 3-D kinematic data are fundamental to a comprehensive understanding of the mechanics, energetics and control of chimpanzee bipedalism.

Electromyography of crural and pedal muscles in tufted capuchin monkeys (Sapajus apella): Implications for hallucal grasping behavior and first metatarsal morphology in euprimates.

A hypertrophied peroneal process of the hallucal metatarsal, as seen in prosimians, has been linked to a powerful hallucal grasp via the contraction of the peroneus longus (PL) muscle causing adduction of the big toe. Electromyography (EMG) studies of lemurs and lorises, however, have concluded that PL is not substantially recruited during small branch locomotion when powerful hallucal grasping is needed most, and have suggested that there is no link between PL activity and peroneal process size. If this is correct, then we should also observe no change in PL activity when strong hallucal grasping is required in anthropoids because they have a relatively smaller peroneal process for PL to act on. This study addresses this hypothesis by evaluating EMG of crural and pedal muscles in capuchins (Sapajus apella) walking on substrates of different diameters. During locomotion on the narrow substrate (3.1 cm) that should elicit a strong hallucal grasp, we observed an intense increased recruitment of adductor hallucis, but only sustained, rather than markedly increased, PL activity. This indicates that PL is not involved in powerful hallucal grasping in capuchins, and confirms similar findings previously documented in prosimians. We continue to reject the hypothesis that a large peroneal process is an adaptation for powerful grasping and further argue that its morphology may not be related to PL's ability to adduct the hallux at all. In addition, the morphology of the peroneal process should not be used to assess hallucal grasping performance in fossils.

Empowering Women's Prenatal Communication: Does Literacy Matter?

This study was designed to evaluate the impact of an interactive computer program developed to empower prenatal communication among women with restricted literacy skills. A total of 83 women seeing 17 clinicians were randomized to a computer-based communication activation intervention (Healthy Babies Healthy Moms [HBHM]) or prenatal education (Baby Basics [BB]) prior to their prenatal visit. Visit communication was coded with the Roter Interaction Analysis System, and postvisit satisfaction was reported. Participants were on average 24 years of age and 25 weeks pregnant; 80% were African American. Two thirds scored ≤8th grade on a literacy screener. Women with literacy deficits were more verbally active, disclosed more medical and psychosocial/lifestyle information, and were rated as more dominant by coders in the HBHM group relative to their counterparts in the BB group (all ps < .05). Clinicians were less verbally dominant and more patient centered with literate HBHM relative to BB group women (p < .05); there was a similar, nonsignificant trend (p < .1) for lower literate women. Clinicians communicated less medical information and made fewer reassurance statements to lower literate women in the HBHM relative to the BB group (p < .05). There was a trend toward lower visit satisfaction for women with restricted literacy in the HBHM relative to the BB group (p < .1); no difference in satisfaction was evident for more literate women. The HBHM intervention empowered communication of all women and facilitated verbal engagement and relevant disclosure of medical and psychosocial information of women with literacy deficits. Satisfaction, however, tended to be lower for these women.

Brief communication: Cineradiographic analysis of the chimpanzee (Pan troglodytes) talonavicular and calcaneocuboid joints.

During terrestrial locomotion, chimpanzees exhibit dorsiflexion of the midfoot between midstance and toe-off of stance phase, a phenomenon that has been called the "midtarsal break." This motion is generally absent during human bipedalism, and in chimpanzees is associated with more mobile foot joints than in humans. However, the contribution of individual foot joints to overall foot mobility in chimpanzees is poorly understood, particularly on the medial side of the foot. The talonavicular (TN) and calcaneocuboid (CC) joints have both been suggested to contribute significantly to midfoot mobility and to the midtarsal break in chimpanzees. To evaluate the relative magnitude of motion that can occur at these joints, we tracked skeletal motion of the hindfoot and midfoot during passive plantarflexion and dorsiflexion manipulations using cineradiography. The sagittal plane range of motion was 38 ± 10° at the TN joint and 14 ± 8° at the CC joint. This finding indicates that the TN joint is more mobile than the CC joint during ankle plantarflexion-dorsiflexion. We suggest that the larger range of motion at the TN joint during dorsiflexion is associated with a rotation (inversion-eversion) across the transverse tarsal joint, which may occur in addition to sagittal plane motion.

Listening in on difficult conversations: an observational, multi-center investigation of real-time conversations in medical oncology.

BACKGROUND: The quality of communication in medical care has been shown to influence health outcomes. Cancer patients, a highly diverse population, communicate with their clinical care team in diverse ways over the course of their care trajectory. Whether that communication happens and how effective it is may relate to a variety of factors including the type of cancer and the patient's position on the cancer care continuum. Yet, many of the routine needs of cancer patients after initial cancer treatment are often not addressed adequately. Our goal is to identify areas of strength and areas for improvement in cancer communication by investigating real-time cancer consultations in a cross section of patient-clinician interactions at diverse study sites. METHODS/DESIGN: In this paper we describe the rationale and approach for an ongoing observational study involving three institutions that will utilize quantitative and qualitative methods and employ a short-term longitudinal, prospective follow-up component to investigate decision-making, key topics, and clinician-patient-companion communication dynamics in clinical oncology. DISCUSSION: Through a comprehensive, real-time approach, we hope to provide the fundamental groundwork from which to promote improved patient-centered communication in cancer care.

Rotator cuff muscle function and its relation to scapular morphology in apes.

It is widely held that many differences among primate species in scapular morphology can be functionally related to differing demands on the shoulder associated with particular locomotor habits. This perspective is largely based on broad scale studies, while more narrow comparisons of scapular form often fail to follow predictions based on inferred differences in shoulder function. For example, the ratio of supraspinous fossa/infraspinous fossa size in apes is commonly viewed as an indicator of the importance of overhead use of the forelimb, yet paradoxically, the African apes, the most terrestrial of the great apes, have higher scapular fossa ratios than the more suspensory orangutan. The recent discovery of several nearly complete early hominin scapular specimens, and their apparent morphological affinities to scapulae of orangutans and gorillas rather than chimpanzees, has led to renewed interest in the comparative analysis of human and extant ape scapular form. To facilitate the functional interpretation of differences in ape scapulae, particularly in regard to relative scapular fossa size, we used electromyography (EMG) to document the activity patterns in all four rotator cuff muscles in orangutans and gibbons, comparing the results with previously published data for chimpanzees. The EMG results indicate that the distinctive contributions of each cuff muscle to locomotion are the same in the three ape species, failing to support inferences of differences in rotator cuff function based on relative scapular fossa size comparisons. It is also shown that relative scapular fossa size is not in fact a good predictor of either the relative masses or cross-sectional areas of the rotator cuff muscles in apes, and relative fossa size gives a false impression of the importance of individual cuff muscles to locomotor differences among apes. A possible explanation for the disparity between fossa and muscle size relates to the underappreciated role of the scapular spine in structural reinforcement of the blade.

A three-dimensional musculoskeletal model of the chimpanzee (Pan troglodytes) pelvis and hind limb.

Musculoskeletal models have become important tools for studying a range of muscle-driven movements. However, most work has been in modern humans, with few applications in other species. Chimpanzees are facultative bipeds and our closest living relatives, and have provided numerous important insights into our own evolution. A chimpanzee musculoskeletal model would allow integration across a wide range of laboratory-based experimental data, providing new insights into the determinants of their locomotor performance capabilities, as well as the origins and evolution of human bipedalism. Here, we described a detailed three-dimensional (3D) musculoskeletal model of the chimpanzee pelvis and hind limb. The model includes geometric representations of bones and joints, as well as 35 muscle-tendon units that were represented using 44 Hill-type muscle models. Muscle architecture data, such as muscle masses, fascicle lengths and pennation angles, were drawn from literature sources. The model permits calculation of 3D muscle moment arms, muscle-tendon lengths and isometric muscle forces over a wide range of joint positions. Muscle-tendon moment arms predicted by the model were generally in good agreement with tendon-excursion estimates from cadaveric specimens. Sensitivity analyses provided information on the parameters that model predictions are most and least sensitive to, which offers important context for interpreting future results obtained with the model. Comparisons with a similar human musculoskeletal model indicate that chimpanzees are better suited for force production over a larger range of joint positions than humans. This study represents an important step in understanding the integrated function of the neuromusculoskeletal systems in chimpanzee locomotion.

Electromyography of wrist and finger flexor muscles in olive baboons (Papio anubis).

Some non-human primates use digitigrade hand postures when walking slowly on the ground. As a component of an extended limb, a digitigrade posture can help minimize wrist joint moments thereby requiring little force production directly from wrist flexors (and/or from the assistance of finger flexors) to maintain limb posture. As a consequence, less active muscle volume would be required from these anti-gravity muscles and overall metabolic costs associated with locomotion could be reduced. To investigate whether the use of digitigrade hand postures during walking in primates entails minimal use of anti-gravity muscles, this study examined electromyography (EMG) patterns in both the wrist and finger flexor muscles in facultatively digitigrade olive baboons (Papio anubis) across a range of speeds. The results demonstrate that baboons can adopt a digitigrade hand posture when standing and moving at slow speeds without requiring substantial EMG activity from distal anti-gravity muscles. Higher speed locomotion, however, entails increasing EMG activity and is accompanied by a dynamic shift to a more palmigrade-like limb posture. Thus, the ability to adopt a digitigrade hand posture by monkeys is an adaptation for ground living, but it was never co-opted for fast locomotion. Rather, digitigrady in primates appears to be related to energetic efficiency for walking long distances.

Communication profiles of psychiatric residents and attending physicians in medication-management appointments: a quantitative pilot study.

OBJECTIVE: The authors quantitatively examined differences in psychiatric residents' and attending physicians' communication profiles and voice tones. METHODS: Audiotaped recordings of 49 resident-patient and 35 attending-patient medication-management appointments at four ambulatory sites were analyzed with the Roter Interaction Analysis System (RIAS). Nonparametric tests were used to compare differences in proportions of speech devoted to relationship-building, activating, and partnering in decision-making processes, and data-gathering/counseling/patient education. Differences in affect expressed by psychiatrists' voice tones were also examined. RESULTS: Residents' visits were twice as long as Attendings' visits (28.2 versus 14.1 minutes), and residents devoted a significantly greater proportion of their talk to relationship-building (23% versus 20%) and activating/partnering (36% versus 28%) aspects of communication, whereas Attendings devoted a greater proportion to biomedically-related data-gathering/counseling/patient education (31% versus 20%). Analysis of voice tones revealed that residents were perceived as sounding significantly friendlier and more sympathetic, versus Attendings, who were rated as sounding more dominant and rushed. CONCLUSION: These findings show distinct communication profiles and voice-tone differences. Future psychiatric communication research should address the influence of appointment length, psychiatrist/patient characteristics, and other potential confounders on psychiatrist-patient communication.

Effects of online genetics education on physician assistant interviewing skills.

OBJECTIVES: This study was designed to evaluate the impact of an Internet-based educational program on clinically relevant communication behaviors. METHODS: A randomized trial enrolled 50 physician assistants (PAs); 40 PAs completed the trial (18 in the intervention group and 22 in the control group). Participants conducted simulated visits that were coded for completeness of family history, referral for genetic services, and overall interviewing style using the Roter Interaction Analysis System (RIAS). RESULTS: Compared with PAs in the control group, PAs who took the Web course elicited more complete family histories (7.2 vs 5.0 of a 13-member pedigree; t = 2.3, P < .05) and more detailed cancer histories (3.2 vs 2.3 of five affected family members; t = 2.7, P < .001) but did not make more genetics referrals. Overall, intervention-group PAs used a less patient-centered interviewing style than controls (1.9 vs 3.2; t = 2.8, P < .01). CONCLUSIONS: More comprehensive assessment of family history was associated with lower patient-centeredness, suggesting a need for caution with regard to unintended consequences of targeted communication interventions on interviewing style.

A randomized trial to improve patient-centered care and hypertension control in underserved primary care patients.

BACKGROUND: African Americans and persons with low socioeconomic status (SES) are disproportionately affected by hypertension and receive less patient-centered care than less vulnerable patient populations. Moreover, continuing medical education (CME) and patient-activation interventions have infrequently been directed to improve the processes of care for these populations. OBJECTIVE: To compare the effectiveness of patient-centered interventions targeting patients and physicians with the effectiveness of minimal interventions for underserved groups. DESIGN: Randomized controlled trial conducted from January 2002 through August 2005, with patient follow-up at 3 and 12 months, in 14 urban, community-based practices in Baltimore, Maryland. PARTICIPANTS: Forty-one primary care physicians and 279 hypertension patients. INTERVENTIONS: Physician communication skills training and patient coaching by community health workers. MAIN MEASURES: Physician communication behaviors; patient ratings of physicians' participatory decision-making (PDM), patient involvement in care (PIC), reported adherence to medications; systolic and diastolic blood pressure (BP) and BP control. KEY RESULTS: Visits of trained versus control group physicians demonstrated more positive communication change scores from baseline (-0.52 vs. -0.82, p = 0.04). At 12 months, the patient+physician intensive group compared to the minimal intervention group showed significantly greater improvements in patient report of physicians' PDM (ß = +6.20 vs. -5.24, p = 0.03) and PIC dimensions related to doctor facilitation (ß = +0.22 vs. -0.17, p = 0.03) and information exchange (ß = +0.32 vs. -0.22, p = 0.005). Improvements in patient adherence and BP control did not differ across groups for the overall patient sample. However, among patients with uncontrolled hypertension at baseline, non-significant reductions in systolic BP were observed among patients in all intervention groups-the patient+physician intensive (-13.2 mmHg), physician intensive/patient minimal (-10.6 mmHg), and the patient intensive/physician minimal (-16.8 mmHg), compared to the patient+physician minimal group (-2.0 mmHg). CONCLUSION: Interventions that enhance physicians' communication skills and activate patients to participate in their care positively affect patient-centered communication, patient perceptions of engagement in care, and may improve systolic BP among urban African-American and low SES patients with uncontrolled hypertension.